Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
125 results · page 1 of 3
Oct 23, 2026A local privilege escalation vulnerability in the optional dnscache package of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to access files wCVE-2026-93640 · Email & office · Zimbra · reported by cve@rapid7.comHigh 7.8
A local privilege escalation vulnerability in the optional dnscache package of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to access files with root privileges. The passwordless sudo policy permits arbitrary arguments to zmunbound, whose wrapper forwards them to Unbound without restricting the configuration path. An attacker can supply a configuration that retains root privileges and disables the chroot. Include directives expose root-readable file contents through parser errors, while an attacker-selected logfile path creates a root-owned file or appends Unbound log records to an existing file. This can disclose password hashes and private keys and corrupt privileged configuration files, preventing affected services from starting with the modified configuration. The affected configuration is present in ZCS 10.1.16 and 10.1.21 dnscache packages.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite gCVE-2026-93639 · Email & office · Zimbra · reported by cve@rapid7.comHigh 8.7
A missing authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows a delegated administrator with no explicit administrative grants to overwrite global Zimlet configuration through ConfigureZimletRequest. The uploaded configuration can also add an attacker-controlled domain to the proxy allowlist of the default class of service. If a signed-in user in that class opens a crafted /service/proxy URL, Zimbra serves attacker-controlled HTML under its own origin. The resulting JavaScript can read mailbox data and perform authenticated actions as the victim. Exploitation requires a delegated-administrator account and access to the admin SOAP service; the browser compromise additionally requires the victim to open the crafted URL. ZCS 10.1.16 and 10.1.20 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A reflected cross-site scripting vulnerability in the login page of Zimbra Collaboration Suite (ZCS) allows an unauthenticated attacker to execute JavaScript thCVE-2026-93638 · Email & office · Zimbra · reported by cve@rapid7.comMedium 6.1
A reflected cross-site scripting vulnerability in the login page of Zimbra Collaboration Suite (ZCS) allows an unauthenticated attacker to execute JavaScript through the zrememberme parameter. A crafted relogin URL selects a two-factor error display that inserts the parameter into a hidden input attribute without HTML encoding. A victim who opens the URL receives attacker-controlled script and page content under the legitimate Zimbra origin, allowing credential capture through a replacement login form. The relogin path logs out an existing session before rendering the payload, so the demonstrated attack does not inherit that session's mailbox access. ZCS 10.1.16 and 10.1.17 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026An LDAP filter injection vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to query otherwise unreturned attributes of calendar resCVE-2026-93636 · Email & office · Zimbra · reported by cve@rapid7.comMedium 4.3
An LDAP filter injection vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to query otherwise unreturned attributes of calendar resources through SearchCalendarResourcesRequest. Zimbra escapes search values but inserts the supplied attribute names directly into LDAP filter expressions without validation. An attacker can inject additional conditions and use repeated matching queries to recover readable resource attributes such as internal mailbox hostnames and mail transport routes. The search remains restricted to calendar-resource objects and the LDAP service account's access rights. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A cross-account authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to insert forged shared-file records into another uCVE-2026-93634 · Email & office · Zimbra · reported by cve@rapid7.comMedium 4.3
A cross-account authorization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to insert forged shared-file records into another user's mailbox through FileSharedWithMeRequest. The request bypasses delegated-account authorization and accepts attacker-selected file metadata, owner identifiers and declared sizes without validating a corresponding document share. An attacker can plant entries attributed to another real local account without that account sharing a document. No victim interaction is required. ZCS 10.1.16 and 10.1.20 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A CSS sanitization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user with Briefcase access to publish a document that displays attaCVE-2026-93633 · Email & office · Zimbra · reported by cve@rapid7.comMedium 5.4
A CSS sanitization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user with Briefcase access to publish a document that displays attacker-controlled content under the Zimbra origin. When processing a stylesheet containing non-ASCII characters, DefangFilter appends the final ASCII segment without sanitizing it. HTML stored as application/x-zimbra-doc can therefore retain CSS URL references that the normal sanitizer removes. An attacker can share a crafted document that loads external resources and displays a credential-collection form using Zimbra's own visual assets. Exploitation requires the victim to open the document in a browser that renders the content type inline; credential theft additionally requires form submission. ZCS 10.1.16 and 10.1.20 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-conCVE-2026-93631 · Email & office · Zimbra · reported by cve@rapid7.comHigh 7.1
A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A hostname canonicalization vulnerability in the email HTML sanitizers of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to bypass the restriCVE-2026-93630 · Email & office · Zimbra · reported by cve@rapid7.comMedium 4.3
A hostname canonicalization vulnerability in the email HTML sanitizers of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to bypass the restriction on forms that target the Zimbra host. DefangFilter and the OWASP ActionAttributePolicy compare the form-action hostname with the request hostname before browser URL canonicalization. A percent-encoded hostname can therefore survive sanitization while the browser submits the form to the normal Zimbra origin with the recipient's authentication cookie. This permits authenticated form requests from a crafted email after the recipient opens it in Classic and submits the form. The issue is present in ZCS 10.1.16 and 10.1.21. It does not bypass an endpoint's CSRF-token checks; a state-changing attack additionally requires an endpoint that accepts the resulting request without that protection.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026An organizer authentication vulnerability in Zimbra Collaboration Suite (ZCS) allows an unauthenticated email sender to insert calendar invitations attributed tCVE-2026-93629 · Email & office · Zimbra · reported by cve@rapid7.comMedium 5.3
An organizer authentication vulnerability in Zimbra Collaboration Suite (ZCS) allows an unauthenticated email sender to insert calendar invitations attributed to another user. The email delivery path permits external invitations but does not verify that the message sender is authorized to use the iCalendar ORGANIZER identity. When automatic invitation insertion is enabled, a crafted REQUEST component creates an event containing attacker-selected meeting details and reminders under a forged organizer without recipient interaction. No corresponding event is created in the claimed organizer's calendar. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026An attendee authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to forge another CVE-2026-93628 · Email & office · Zimbra · reported by cve@rapid7.comMedium 5.3
An attendee authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to forge another attendee's response to an existing meeting. Zimbra passes a null sender identity when processing iCalendar REPLY components, causing the attendee authorization filter to be skipped. An attacker who knows the meeting UID, organizer address and attendee address can send a non-outdated reply that changes the attendee's participation status in the organizer's calendar. The change occurs automatically during delivery without organizer or attendee interaction. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026An organizer authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to cancel or modCVE-2026-93627 · Email & office · Zimbra · reported by cve@rapid7.comMedium 5.3
An organizer authentication vulnerability in the email calendar processing of Zimbra Collaboration Suite (ZCS) allows an unauthenticated sender to cancel or modify an existing meeting in a recipient's calendar. Zimbra accepts iCalendar CANCEL and REQUEST components without verifying that the email sender is authorized to act as the supplied organizer. An attacker who knows the meeting UID and organizer address can supply a non-outdated sequence number to move the recipient's meeting to Trash or replace its details. Processing occurs automatically during email delivery without recipient interaction. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A local privilege escalation vulnerability in the Zimbra Collaboration Suite (ZCS) MTA package allows the Unix zimbra account to execute arbitrary commands as rCVE-2026-50057 · Email & office · Zimbra · reported by cve@rapid7.comHigh 7.8
A local privilege escalation vulnerability in the Zimbra Collaboration Suite (ZCS) MTA package allows the Unix zimbra account to execute arbitrary commands as root. The installed sudo policy permits passwordless root execution of Postfix administration commands without restricting their arguments. An attacker can select a zimbra-controlled daemon_directory in the Postfix configuration and invoke postfix set-permissions, causing Postfix to execute the attacker's post-install program as root. The Postfix configuration directory is also writable by zimbra, so restricting postconf alone does not remove the execution path. Exploitation requires local command execution as zimbra on an MTA node. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A local privilege escalation vulnerability in the zmmailboxdmgr launcher of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to execute arbitraryCVE-2026-50056 · Email & office · Zimbra · reported by cve@rapid7.comHigh 7.8
A local privilege escalation vulnerability in the zmmailboxdmgr launcher of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to execute arbitrary commands as root. The passwordless sudo interface accepts JVM arguments that are not adequately restricted. An attacker can postpone Jetty's privilege drop, register an OnOutOfMemoryError command and force heap exhaustion during startup, causing the command to execute while the JVM still runs as root. Exploitation requires local command execution as zimbra on a mailbox server and interrupts mailboxd during the malicious restart. ZCS 10.1.16 and 10.1.21 are affected.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A request attribute override vulnerability in Zimbra Collaboration Suite (ZCS) allows unauthenticated requests to /h/* to populate servlet attributes intended fCVE-2026-50053 · Email & office · Zimbra · reported by cve@rapid7.comHigh 8.7
A request attribute override vulnerability in Zimbra Collaboration Suite (ZCS) allows unauthenticated requests to /h/* to populate servlet attributes intended for trusted internal dispatch. RestFilter copies URL parameters specifying an authentication token, target account, target item and dispatch state into the request attributes consumed by the Classic Web Client. Combined with CVE-2026-10632 on ZCS 10.1.16, this allows an attacker to supply their own valid token and document identifiers and execute JavaScript in another user's signed-in browser session. ZCS 10.1.17 blocks that XSS chain by changing the document renderer, but retains the request attribute override.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A mailbox quota-accounting vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to consume another user’s mailbox quota by repeatedly CVE-2026-115786 · Email & office · Zimbra · reported by cve@rapid7.comMedium 6.5
A mailbox quota-accounting vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to consume another user’s mailbox quota by repeatedly sharing and revoking a document. Creation of the recipient’s shared-file record charges the document size to mailbox-wide usage. Revocation deletes the record and reverses its folder counters without reversing the mailbox-wide charge. Repeated normal share notifications therefore accumulate quota usage after the visible records are gone. On accounts with a finite quota, this can prevent incoming mail and other size-increasing operations without recipient interaction. The issue affects ZCS 10.1.16 and 10.1.20.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026An SMTP command injection vulnerability in the data-source testing functionality of Zimbra Collaboration Suite (ZCS) allows an ordinary authenticated user with CVE-2026-115785 · Email & office · Zimbra · reported by cve@rapid7.comMedium 4.3
An SMTP command injection vulnerability in the data-source testing functionality of Zimbra Collaboration Suite (ZCS) allows an ordinary authenticated user with account options enabled to inject CR/LF into the emailAddress inserted into an SMTP envelope command by a JSON SOAP request. After a successful preliminary POP3 or IMAP login, Zimbra sends the injected commands to the selected SMTP service. If that service accepts the pipelined transaction, the attacker can submit mail with attacker-selected recipients, headers and body content without victim interaction. The vulnerable command-construction path is present in ZCS 10.1.16 and 10.1.20.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 23, 2026A reflected cross-site scripting vulnerability in the Classic Web Client of Zimbra Collaboration Suite (ZCS) allows an attacker to inject JavaScript through theCVE-2026-10632 · Email & office · Zimbra · reported by cve@rapid7.comHigh 8.7
A reflected cross-site scripting vulnerability in the Classic Web Client of Zimbra Collaboration Suite (ZCS) allows an attacker to inject JavaScript through the packages parameter of the /h/rest document editor. The editor inserts package names into script attributes without HTML encoding. When combined with CVE-2026-50053, an attacker with an ordinary Zimbra account can supply their own authentication token and document identifiers in a URL and execute JavaScript in another signed-in user's Zimbra browser session when that user opens the URL. This permits reading mailbox data and performing authenticated actions as the victim. The issue affects ZCS 10.1.16 and was remediated in 10.1.17.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comrapid7.com
Oct 14, 2026An authentication rate-limit bypass in Zimbra Collaboration Suite 10.1.0 through 10.1.21 allows unauthenticated attackers to make repeated password guesses throCVE-2026-93637 · Email & office · Zimbra · reported by cve@rapid7.comLow 3.7
An authentication rate-limit bypass in Zimbra Collaboration Suite 10.1.0 through 10.1.21 allows unauthenticated attackers to make repeated password guesses through GraphQL without incrementing Zimbra’s source-IP failure counter. GraphQL aliases allow multiple authentication attempts in one HTTP request.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 14, 2026LDAP filter injection in Zimbra Collaboration Suite 10.1.0 through 10.1.21 allows unauthenticated attackers to alter external LDAP search filters.CVE-2026-93635 · Email & office · Zimbra · reported by cve@rapid7.comMedium 5.3
LDAP filter injection in Zimbra Collaboration Suite 10.1.0 through 10.1.21 allows unauthenticated attackers to alter external LDAP search filters. On domains using search-filter authentication and lazy provisioning, this creates a password oracle for external directory users. Authenticated S/MIME lookups can also return certificates and identity data for unintended directory entries.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026A policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send cCVE-2026-50055 · Email & office · Zimbra · reported by cve@rapid7.comMedium 6.5
A policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send copies of email content and headers to an arbitrary address.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026An authorization flaw in Zimbra Collaboration Suite’s GrantRightsRequest allows an attacker with access to an authenticated account to grant another local accouCVE-2026-50054 · Email & office · Zimbra · reported by cve@rapid7.comHigh 7.1
An authorization flaw in Zimbra Collaboration Suite’s GrantRightsRequest allows an attacker with access to an authenticated account to grant another local account the loginAs right, creating persistent mailbox access and mail-sending authority that survives password changes and session expiry.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read cCVE-2026-10631 · Email & office · Zimbra · reported by cve@rapid7.comMedium 6.5
An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary local accounts without a share or delegation grant.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 25, 2026An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address.CVE-2026-93647 · Email & office · Zimbra · reported by cve@rapid7.comCritical 9.3
An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim.
- Product
- Zimbra Collaboration Suite (ZCS)
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 25, 2026When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigCVE-2026-93643 · Email & office · Zimbra · reported by cve@rapid7.comCritical 9.8
When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigned save fields to perform path-traversal writes and execute commands as zimbra.
- Product
- Zimbra Collaboration Suite (ZCS)
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 25, 2026An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attCVE-2026-93642 · Email & office · Zimbra · reported by cve@rapid7.comCritical 9.3
An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
- Product
- Zimbra Collaboration Suite (ZCS)
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 25, 2026An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Classic recipient clicks Accept Share, allowing the atCVE-2026-93641 · Email & office · Zimbra · reported by cve@rapid7.comCritical 9.3
An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Classic recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
- Product
- Zimbra Collaboration Suite (ZCS)
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Zimbra Collaboration Suite (ZCS) OS Command Injection VulnerabilityCVE-2026-73570 · Email & office · Synacor · reported by MITREExploitedHigh 8.9
Zimbra Collaboration Suite (ZCS) contains an OS command injection vulnerability which could allow an unauthenticated attacker to send specially crafted SMTP requests that may result in execution of arbitrary operating system commands as the Zimbra user.
- Product
- Zimbra Collaboration Suite (ZCS)
- On CISA’s list since
- Aug 21, 2026 (federal fix deadline Aug 24, 2026)
- What to do
- Attackers are using this now. Install Synacor’s update today. If there is no update for your version, take the product off the internet or stop using it until there is.
Full record and what to do →NVD recordCISA catalogwiki.zimbra.comwiki.zimbra.com
Mar 30, 2026An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.CVE-2026-33373 · Email & office · Synacor · reported by MITREHigh 8.8
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A Cross-Site Request Forgery (CSRF) vulnerability exists in Zimbra Web Client due to the issuance of authentication tokens without CSRF protection during certain account state transitions. Specifically, tokens generated after operations such as enabling two-factor authentication or changing a password may lack CSRF enforcement. While such a token is active, authenticated SOAP requests that trigger token generation or state changes can be performed without CSRF validation. An attacker could exploit this by inducing a victim to submit crafted requests, potentially allowing sensitive account actions such as disabling two-factor authentication. The issue is mitigated by ensuring CSRF protection is consistently enforced for all issued authentication tokens.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 20, 2026An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.CVE-2026-33372 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A cross-site request forgery (CSRF) vulnerability exists in Zimbra Webmail due to improper validation of CSRF tokens. The application accepts CSRF tokens supplied within the request body instead of requiring them through the expected request header. An attacker can exploit this issue by tricking an authenticated user into submitting a crafted request. This may allow unauthorized actions to be performed on behalf of the victim.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 20, 2026An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.CVE-2026-33371 · Email & office · Synacor · reported by MITREMedium 4.3
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. An XML External Entity (XXE) vulnerability exists in the Zimbra Exchange Web Services (EWS) SOAP interface due to improper handling of XML input. An authenticated attacker can submit crafted XML data that is processed by an XML parser with external entity resolution enabled. Successful exploitation may allow disclosure of sensitive local files from the server.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 20, 2026An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.CVE-2026-33370 · Email & office · Synacor · reported by MITREMedium 6.1
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Zimbra Briefcase feature due to insufficient sanitization of specific uploaded file types. When a user opens a publicly shared Briefcase file containing malicious scripts, the embedded JavaScript executes in the context of the user's session. This allows an attacker to run arbitrary scripts, potentially leading to data exfiltration or other unauthorized actions on behalf of the victim user.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 20, 2026Zimbra Collaboration (ZCS) 10.0 and 10.1 contains an LDAP injection vulnerability in the Mailbox SOAP service within a FolderAction operation.CVE-2026-33369 · Email & office · Synacor · reported by MITREMedium 4.3
Zimbra Collaboration (ZCS) 10.0 and 10.1 contains an LDAP injection vulnerability in the Mailbox SOAP service within a FolderAction operation. The application fails to properly sanitize user-supplied input before incorporating it into an LDAP search filter. An authenticated attacker can exploit this issue by sending a crafted SOAP request that manipulates the LDAP query, allowing retrieval of sensitive directory attributes.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 20, 2026Zimbra Collaboration Suite (ZCS) 10.0 and 10.1 contains a reflected cross-site scripting (XSS) vulnerability in the Classic Webmail REST interface (/h/rest).CVE-2026-33368 · Email & office · Synacor · reported by MITREMedium 6.1
Zimbra Collaboration Suite (ZCS) 10.0 and 10.1 contains a reflected cross-site scripting (XSS) vulnerability in the Classic Webmail REST interface (/h/rest). The application fails to properly sanitize user-supplied input, allowing an unauthenticated attacker to inject malicious JavaScript into a crafted URL. When a victim user accesses the link, the injected script executes in the context of the Zimbra webmail application, which could allow the attacker to perform actions on behalf of the victim.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Jan 5, 2026Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting VulnerabilityCVE-2025-66376 · Email & office · Synacor · reported by MITREExploitedHigh 7.2
Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability in the Classic UI where attackers could abuse Cascading Style Sheets (CSS) @import directives in email HTML.
- Product
- Zimbra Collaboration Suite (ZCS)
- On CISA’s list since
- Mar 18, 2026 (federal fix deadline Apr 1, 2026)
- What to do
- Attackers are using this now. Install Synacor’s update today. If there is no update for your version, take the product off the internet or stop using it until there is.
Full record and what to do →NVD recordCISA catalogwiki.zimbra.comwiki.zimbra.com
Dec 22, 2025Synacor Zimbra Collaboration Suite (ZCS) PHP Remote File Inclusion VulnerabilityCVE-2025-68645 · Email & office · Synacor · reported by MITREExploitedHigh 8.8
Synacor Zimbra Collaboration Suite (ZCS) contains a PHP remote file inclusion vulnerability that could allow for remote attackers to craft requests to the /h/rest endpoint to influence internal request dispatching, allowing inclusion of arbitrary files from the WebRoot directory.
- Product
- Zimbra Collaboration Suite (ZCS)
- On CISA’s list since
- Jan 22, 2026 (federal fix deadline Feb 12, 2026)
- What to do
- Attackers are using this now. Install Synacor’s update today. If there is no update for your version, take the product off the internet or stop using it until there is.
Full record and what to do →NVD recordCISA catalogwiki.zimbra.comwiki.zimbra.com
Jun 23, 2025Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting VulnerabilityCVE-2025-48700 · Email & office · Synacor · reported by MITREExploitedMedium 6.1
Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that could allow attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information.
- Product
- Zimbra Collaboration Suite (ZCS)
- On CISA’s list since
- Apr 20, 2026 (federal fix deadline Apr 23, 2026)
- What to do
- Attackers are using this now. Install Synacor’s update today. If there is no update for your version, take the product off the internet or stop using it until there is.
Full record and what to do →NVD recordCISA catalogwiki.zimbra.comwiki.zimbra.com
May 14, 2025An issue was discovered in Zimbra Collaboration (ZCS) 9.0.0 before Patch 43, 10.0.x before 10.0.12, 10.1.x before 10.1.4, and 8.8.15 before Patch 47.CVE-2024-45516 · Email & office · Synacor · reported by MITREMedium 6.1
An issue was discovered in Zimbra Collaboration (ZCS) 9.0.0 before Patch 43, 10.0.x before 10.0.12, 10.1.x before 10.1.4, and 8.8.15 before Patch 47. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information. This issue arises from insufficient sanitization of HTML content, including malformed <img> tags with embedded JavaScript. The vulnerability is triggered when a user views a specially crafted email in the Classic UI, requiring no additional user interaction.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Apr 29, 2025In Zimbra Collaboration (ZCS) 9.0 through 10.1, a Cross-Site Request Forgery (CSRF) vulnerability exists in the GraphQL endpoint (/service/extension/graphql) ofCVE-2025-32354 · Email & office · Synacor · reported by MITREHigh 8.8
In Zimbra Collaboration (ZCS) 9.0 through 10.1, a Cross-Site Request Forgery (CSRF) vulnerability exists in the GraphQL endpoint (/service/extension/graphql) of Zimbra webmail due to a lack of CSRF token validation. This allows attackers to perform unauthorized GraphQL operations, such as modifying contacts, changing account settings, and accessing sensitive user data when an authenticated user visits a malicious website.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Mar 12, 2025Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting VulnerabilityCVE-2025-27915 · Email & office · Synacor · reported by MITREExploitedMedium 5.4
Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that exists in the Classic Web Client due to insufficient sanitization of HTML content in ICS files. When a user views an e-mail message containing a malicious ICS entry, its embedded JavaScript executes via an ontoggle event inside a tag. This allows an attacker to run arbitrary JavaScript within the victim's session, potentially leading to unauthorized actions such as setting e-mail filters to redirect messages to an attacker-controlled address. As a result, an attacker can perform unauthorized actions on the victim's account, including e-mail redirection and data exfiltration.
- Product
- Zimbra Collaboration Suite (ZCS)
- On CISA’s list since
- Oct 7, 2025 (federal fix deadline Oct 28, 2025)
- What to do
- Attackers are using this now. Install Synacor’s update today. If there is no update for your version, take the product off the internet or stop using it until there is.
Full record and what to do →NVD recordCISA catalogwiki.zimbra.comwiki.zimbra.com
Feb 3, 2025SSRF vulnerability in the RSS feed parser in Zimbra Collaboration 9.0.0 before Patch 43, 10.0.x before 10.0.12, and 10.1.x before 10.1.4 allows unauthorized redCVE-2025-25065 · Email & office · Synacor · reported by MITREMedium 5.3
SSRF vulnerability in the RSS feed parser in Zimbra Collaboration 9.0.0 before Patch 43, 10.0.x before 10.0.12, and 10.1.x before 10.1.4 allows unauthorized redirection to internal network endpoints.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Feb 3, 2025SQL injection vulnerability in the ZimbraSync Service SOAP endpoint in Zimbra Collaboration 10.0.x before 10.0.12 and 10.1.x before 10.1.4 due to insufficient sCVE-2025-25064 · Email & office · Synacor · reported by MITREHigh 8.8
SQL injection vulnerability in the ZimbraSync Service SOAP endpoint in Zimbra Collaboration 10.0.x before 10.0.12 and 10.1.x before 10.1.4 due to insufficient sanitization of a user-supplied parameter. Authenticated attackers can exploit this vulnerability by manipulating a specific parameter in the request, allowing them to inject arbitrary SQL queries that could retrieve email metadata.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Dec 19, 2024An issue was discovered in the Webmail Classic UI in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1.CVE-2024-54663 · Email & office · Synacor · reported by MITREHigh 7.5
An issue was discovered in the Webmail Classic UI in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A Local File Inclusion (LFI) vulnerability exists in the /h/rest endpoint, allowing authenticated remote attackers to include and access sensitive files in the WebRoot directory. Exploitation requires a valid auth token and involves crafting a malicious request targeting specific file paths.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 21, 2024An issue was discovered in Zimbra Collaboration (ZCS) through 10.1.CVE-2024-45517 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in Zimbra Collaboration (ZCS) through 10.1. A Cross-Site Scripting (XSS) vulnerability in the /h/rest endpoint of the Zimbra webmail and admin panel interfaces allows attackers to execute arbitrary JavaScript in the victim's session. This issue is caused by improper sanitization of user input, leading to potential compromise of sensitive information. Exploitation requires user interaction to access the malicious URL.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 21, 2024An issue was discovered in Zimbra Collaboration (ZCS) through 10.1.CVE-2024-45513 · Email & office · Synacor · reported by MITREMedium 4.8
An issue was discovered in Zimbra Collaboration (ZCS) through 10.1. A stored Cross-Site Scripting (XSS) vulnerability exists in the /modern/contacts/print endpoint of Zimbra webmail. This allows an attacker to inject and execute arbitrary JavaScript code in the context of the victim's browser when a crafted vCard (VCF) file is processed and printed. This could lead to unauthorized actions within the victim's session.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 21, 2024In Zimbra Collaboration (ZCS) 9.0 and 10.0, a vulnerability in the Webmail Modern UI allows execution of stored Cross-Site Scripting (XSS) payloads.CVE-2024-45194 · Email & office · Synacor · reported by MITREMedium 4.8
In Zimbra Collaboration (ZCS) 9.0 and 10.0, a vulnerability in the Webmail Modern UI allows execution of stored Cross-Site Scripting (XSS) payloads. An attacker with administrative access to the Zimbra Administration Panel can inject malicious JavaScript code while configuring an email account. This injected code is stored on the server and executed in the context of the victim's browser when interacting with specific elements in the web interface. (The vulnerability can be mitigated by properly sanitizing input parameters to prevent the injection of malicious code.)
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 21, 2024An issue was discovered in Zimbra Collaboration (ZCS) through v10.1.CVE-2024-45514 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in Zimbra Collaboration (ZCS) through v10.1. A Cross-Site Scripting (XSS) vulnerability exists in one of the endpoints of Zimbra Webmail due to insufficient sanitization of the packages parameter. Attackers can bypass the existing checks by using encoded characters, allowing the injection and execution of arbitrary JavaScript within a victim's session.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 21, 2024An issue was discovered in webmail in Zimbra Collaboration (ZCS) through 10.1.CVE-2024-45512 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in webmail in Zimbra Collaboration (ZCS) through 10.1. An attacker can exploit this vulnerability by creating a folder in the Briefcase module with a malicious payload and sharing it with a victim. When the victim interacts with the folder share notification, the malicious script executes in their browser. This stored Cross-Site Scripting (XSS) vulnerability can lead to unauthorized actions within the victim's session.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 20, 2024An issue was discovered in Zimbra Collaboration (ZCS) through 10.0.CVE-2024-45510 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in Zimbra Collaboration (ZCS) through 10.0. Zimbra Webmail (Modern UI) is vulnerable to a stored Cross-Site Scripting (XSS) attack due to improper sanitization of user input. This allows an attacker to inject malicious code into specific fields of an e-mail message. When the victim adds the attacker to their contacts, the malicious code is stored and executed when viewing the contact list. This can lead to unauthorized actions such as arbitrary mail sending, mailbox exfiltration, profile picture alteration, and other malicious actions. Proper sanitization and escaping of input fields are necessary to mitigate this vulnerability.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 20, 2024An issue was discovered in Zimbra Collaboration (ZCS) through 10.1.CVE-2024-45511 · Email & office · Synacor · reported by MITREMedium 5.4
An issue was discovered in Zimbra Collaboration (ZCS) through 10.1. A reflected Cross-Site Scripting (XSS) issue exists through the Briefcase module due to improper sanitization of file content by the OnlyOffice formatter. This occurs when the victim opens a crafted URL pointing to a shared folder containing a malicious file uploaded by the attacker. The vulnerability allows the attacker to execute arbitrary JavaScript in the context of the victim's session.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Nov 7, 2024A reflected Cross-Site Scripting (XSS) vulnerability has been identified in Zimbra Collaboration Suite (ZCS) 8.8.15, affecting one of the webmail calendar endpoCVE-2024-50599 · Email & office · Synacor · reported by MITREMedium 6.1
A reflected Cross-Site Scripting (XSS) vulnerability has been identified in Zimbra Collaboration Suite (ZCS) 8.8.15, affecting one of the webmail calendar endpoints. This arises from improper handling of user-supplied input, allowing an attacker to inject malicious code that is reflected back in the HTML response.
- Product
- Zimbra Collaboration Suite
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordwiki.zimbra.comwiki.zimbra.com
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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