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.
476 results · page 1 of 10
Oct 28, 2026GoSMTP: Does not perform a settings-management authorization check on its SMTP configuration pageCVE-2026-111577 · WordPress plugins & themes · reported by WPScanHigh 7.2
The GoSMTP WordPress plugin before 1.2.5 does not perform a settings-management authorization check on its SMTP configuration page, which is gated only on the GoSMTP WordPress plugin before 1.2.5-activation capability, allowing users with a delegated role below administrator to change outbound mail delivery and achieve administrator account takeover.
- Product
- GoSMTP
- Fixed in
- 1.2.5
- What to do
- Update GoSMTP to 1.2.5 or newer.
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 21, 2026Multiple Cisco products are affected by a vulnerability in the Snort 3 SMTP MIME Decoder that could allow an unauthenticated, remote attacker to cause the SnortCVE-2026-20011 · Network & remote access · Cisco · reported by psirt@cisco.comMedium 5.8
Multiple Cisco products are affected by a vulnerability in the Snort 3 SMTP MIME Decoder that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart. This vulnerability is due to a lack of error checking when the MIME fields of the SMTP header are parsed. An attacker could exploit this vulnerability by sending crafted SMTP packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine unexpectedly restarts.
- Product
- Cisco Open Source Snort3
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordsec.cloudapps.cisco.com
Oct 21, 2026Insertion of sensitive information into a log file in the SMTP server of Progressive Robot hMailServer 6.0.0 through 6.3.6 allows a local user who can read the CVE-2026-114471 · Other software · Progressive Robot Ltd · reported by cve@gitlab.comMedium 4.7
Insertion of sensitive information into a log file in the SMTP server of Progressive Robot hMailServer 6.0.0 through 6.3.6 allows a local user who can read the server's log, or anyone given a copy of it, to obtain credentials. With SMTP logging enabled, the server hid the credential of an AUTH PLAIN command only when it was sent after EHLO in one exact form, and wrote the rest of the SASL exchange as the client sent it: a PLAIN password sent before EHLO or with extra spacing, the OAuth 2.0 bearer token of AUTH XOAUTH2 and AUTH OAUTHBEARER (from 6.2.0), the SCRAM-SHA-256 client proof (from 6.2.0), which with the logged salt and iteration count allows offline password guessing, and the GSSAPI authenticator (from 6.3.2). SMTP logging is off by default; on Windows before 6.3.6 the log folder was readable by every local user.
- Product
- hMailServer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 20, 2026By permanently omitting the final control-response line, a malicious FTP, IMAP, POP3, or SMTP server can exploit libcurl and completely bypass its configured trCVE-2026-92387 · Other software · curl · reported by 2499f714-1537-4658-8207-48ae4bb9eae9High 8.1
By permanently omitting the final control-response line, a malicious FTP, IMAP, POP3, or SMTP server can exploit libcurl and completely bypass its configured transfer timeout mechanism, indefinitely blocking all concurrent transfers bound to the same multi-handle.
- Product
- curl
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 20, 2026When authenticating to a POP3 or SMTP server using NTLM, Thunderbird did not check whether the server's challenge was valid base64.CVE-2026-113868 · Computers, phones & browsers · Mozilla · reported by security@mozilla.orgMedium 5.3
When authenticating to a POP3 or SMTP server using NTLM, Thunderbird did not check whether the server's challenge was valid base64. A malicious server could send a challenge that caused Thunderbird to include uninitialized heap memory in its NTLM response, disclosing that memory to the server. A challenge consisting only of base64 padding also caused an out-of-bounds read, crashing Thunderbird. This affected accounts configured to use NTLM or GSSAPI authentication. The uninitialized memory disclosure only affected NTLM. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
- Product
- Thunderbird
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordbugzilla.mozilla.orgmozilla.org
Oct 16, 2026GoSMTP Pro: Stored Cross-Site ScriptingCVE-2026-96768 · WordPress plugins & themes · reported by WordfenceHigh 7.2
The GoSMTP Pro plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content via Email Log Body in all versions up to, and including, 1.2.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploit is made possible because WordPress comment kses does not strip entity-encoded tag delimiters, allowing the payload to pass moderation as safe text before being decoded into live HTML by core email notification functions and written verbatim into the plugin's email log database table.
- Product
- GoSMTP Pro
- Affected
- up to 1.2.3
- What to do
- Affects up to 1.2.3. Update GoSMTP Pro to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Full record and what to do →NVD recordgosmtp.networdfence.com
Oct 16, 2026YaySMTP – WP Mail SMTP with Email Logs, Tracking & Reports: Arbitrary File UploadCVE-2026-92553 · WordPress plugins & themes · reported by WordfenceHigh 8.8
The YaySMTP – WP Mail SMTP with Email Logs, Tracking & Reports plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.7.7 via the putFile function. This is due to insufficient file type validation in the putFile function, as sanitize_file_name() does not strip executable extensions and no allow-list, MIME check, or safe-extension rename is applied. This makes it possible for authenticated attackers, with subscriber-level access and above, to upload files that may be executable, which makes remote code execution possible. The only server-side guard is a .htaccess file containing 'Require all denied' written by writeGuards(), which is silently ignored by nginx and by Apache configured with AllowOverride None, meaning RCE is fully achievable on those server configurations.
- Product
- YaySMTP – WP Mail SMTP with Email Logs, Tracking & Reports
- Affected
- up to 2.7.7
- What to do
- Affects up to 2.7.7. Update YaySMTP – WP Mail SMTP with Email Logs, Tracking & Reports to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Full record and what to do →NVD recordplugins.trac.wordpress.orgplugins.trac.wordpress.org
Oct 14, 2026Nodemailer from 3.0.0 before 10.0.10 contains a quadratic complexity denial of service vulnerability in the SMTP client reply parser in SMTPConnection._onData aCVE-2026-110872 · Other software · nodemailer · reported by VulnCheckHigh 8.2
Nodemailer from 3.0.0 before 10.0.10 contains a quadratic complexity denial of service vulnerability in the SMTP client reply parser in SMTPConnection._onData and isPartialResponse. A malicious SMTP server or on-path attacker can stream continuation lines without a completion line before authentication, blocking the Node.js event loop and exhausting memory.
- Product
- nodemailer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Oct 14, 2026Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain ovCVE-2026-110869 · Other software · nodemailer · reported by VulnCheckHigh 8.7
Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain overlapping whitespace sub-patterns that backtrack quadratically. A malicious or man-in-the-middle SMTP server can reply to EHLO with 250-AUTH, a long whitespace run and a non-matching token, blocking the Node.js event loop for tens of seconds to hours before authentication.
- Product
- nodemailer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Oct 9, 2026lwIP SMTP client does not check the size of inputs, potentially allowing a buffer overflow.CVE-2026-15340 · Other software · Savannah · reported by ics-cert@hq.dhs.govCritical 9.3
lwIP SMTP client does not check the size of inputs, potentially allowing a buffer overflow.
- Product
- lwIP SMTP client
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 9, 2026AcyMailing SMTP Newsletter: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')CVE-2026-105318 · WordPress plugins & themes · reported by PatchstackHigh 7.1
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Datasolution AcyMailing SMTP Newsletter acymailing allows Reflected XSS.This issue affects AcyMailing SMTP Newsletter: from n/a through 11.1.0.
- Product
- AcyMailing SMTP Newsletter
- Affected
- up to 11.1.0
- What to do
- Affects up to 11.1.0. Update AcyMailing SMTP Newsletter to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Oct 8, 2026Progressive Robot hMailServer 6.0.0 through 6.3.5 fails open when applying DANE (RFC 7672) to outbound SMTP delivery.CVE-2026-107584 · Other software · Progressive Robot Ltd · reported by cve@gitlab.comHigh 7.4
Progressive Robot hMailServer 6.0.0 through 6.3.5 fails open when applying DANE (RFC 7672) to outbound SMTP delivery. The server's validating DNSSEC resolver treated a TLSA or MX lookup that did not complete (no answer, SERVFAIL, a malformed reply), an answer without the requested records and without an NSEC/NSEC3 proof of their absence, and an answer whose records carried no applicable RRSIG as if the recipient domain were unsigned, and from 6.2.19 it also delivered to mail exchangers taken from an unvalidated MX lookup that the DNSSEC-validated MX record set did not name. An attacker who can drop, forge or strip DNS answers on the path to the server's resolver, at the resolver, or between the resolver and the recipient domain's name servers, and who holds an active position on the SMTP path, can thereby disable DANE for a DNSSEC-signed recipient domain and cause messages to be delivered in cleartext or to a host of the attacker's choosing with an arbitrary certificate, where they can be read and modified.
- Product
- hMailServer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026Progressive Robot hMailServer 6.0.0 through 6.3.5 does not enforce TLS for outbound SMTP delivery to a mail exchanger whose DNSSEC-validated TLSA records contaiCVE-2026-104704 · Other software · Progressive Robot Ltd · reported by cve@gitlab.comHigh 7.4
Progressive Robot hMailServer 6.0.0 through 6.3.5 does not enforce TLS for outbound SMTP delivery to a mail exchanger whose DNSSEC-validated TLSA records contain no DANE-EE (usage 3) record, contrary to RFC 7672 section 2.2. The server used only DANE-EE records and treated a validated TLSA record set consisting of DANE-TA (usage 2) or otherwise unusable records as if no records were published, so delivery to such a host fell back to opportunistic TLS. An attacker with an active position on the network path between the server and the recipient's mail exchanger can suppress or break the STARTTLS negotiation and cause messages to be delivered in cleartext, where they can be read and modified.
- Product
- hMailServer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 7, 2026Authenticated users are able to manipulate both the SMTP envelope “Envelope-from” and “From” fields when sending emails through OVH mail servers.CVE-2026-33586 · Other software · OVHcloud · reported by a6d3dc9e-0591-4a13-bce7-0f5b31ff6158Medium 6.3
Authenticated users are able to manipulate both the SMTP envelope “Envelope-from” and “From” fields when sending emails through OVH mail servers. Due to OVH's default SPF configuration, which commonly includes include:mx.ovh.com, any authenticated user with a valid OVH email account can send messages that appear to originate from any OVH-hosted domains using the default SPF record. Since the SPF policy explicitly authorizes OVH mail servers (mx.ovh.com) to send mail on behalf of these domains, forged messages successfully pass SPF validation despite not being authorized by the impersonated domain owner.
- Product
- OVHcloud
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 7, 2026Gophish through 0.12.1 contains stored and reflected cross-site scripting vulnerabilities that allow attackers to inject script by returning malicious SMTP servCVE-2026-107272 · Other software · gophish · reported by VulnCheckLow 2.3
Gophish through 0.12.1 contains stored and reflected cross-site scripting vulnerabilities that allow attackers to inject script by returning malicious SMTP server error messages. Attackers controlling or intercepting a sending profile's SMTP server can execute script when administrators view campaign results or send test emails, stealing API keys.
- Product
- gophish
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordblog.ostorlab.cogithub.com
Oct 7, 2026A flaw was found in the SMTP email configuration handling of the keycloak-services component.CVE-2026-107121 · Other software · Red Hat · reported by Red HatMedium 6.5
A flaw was found in the SMTP email configuration handling of the keycloak-services component. When the STARTTLS option is enabled, Keycloak fails to strictly enforce an encrypted connection, allowing it to fall back to unencrypted communication if the encryption request is tampered with. An attacker who can intercept network traffic can exploit this to capture sensitive email credentials and message content in plain text.
- Product
- Red Hat Build of Keycloak
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordaccess.redhat.combugzilla.redhat.com
Oct 6, 2026Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net.CVE-2026-105241 · Websites & servers · Apache Software Foundation · reported by security@apache.orgMedium 5.3
Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content, and a truncated mail could be left in the pickup directory. A party whose data reaches a log message could suppress the records of other events. Only applications that use SmtpPickupDirAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.
- Product
- Apache log4net
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 6, 2026Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App: Stored Cross-Site ScriptingCVE-2026-75962 · WordPress plugins & themes · reported by WordfenceHigh 7.2
The Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'user_email' parameter in all versions up to, and including, 4.0.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is exploitable without authentication on WordPress Multisite installations with public registration enabled, as WordPress accepts email addresses containing numeric HTML character references that Post SMTP's stricter validator rejects, persisting the attacker-controlled address verbatim to the email log via the failed-send exception message.
- Product
- Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
- Affected
- up to 4.0.1
- What to do
- Affects up to 4.0.1. Update Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Full record and what to do →NVD recordplugins.trac.wordpress.orgplugins.trac.wordpress.org
Oct 1, 2026Unauthenticated Arbitrary File Deletion in AcyMailing SMTP Newsletter <= 11.0.5 versions.CVE-2026-95588 · WordPress plugins & themes · reported by PatchstackHigh 8.6
Unauthenticated Arbitrary File Deletion in AcyMailing SMTP Newsletter <= 11.0.5 versions.
- Affected
- up to 11.0.5
- What to do
- Affects up to 11.0.5. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Sep 30, 2026In JetBrains YouTrack before 2026.2.18991 stored SMTP server credentials could be disclosed by changing the server hostCVE-2026-100264 · Other software · JetBrains · reported by cve@jetbrains.comLow 2.7
In JetBrains YouTrack before 2026.2.18991 stored SMTP server credentials could be disclosed by changing the server host
- Product
- YouTrack
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 30, 2026Unauthenticated Remote Code Execution (RCE) in AcyMailing SMTP Newsletter <= 11.0.5 versions.CVE-2026-94389 · WordPress plugins & themes · reported by PatchstackCritical 9
Unauthenticated Remote Code Execution (RCE) in AcyMailing SMTP Newsletter <= 11.0.5 versions.
- Affected
- up to 11.0.5
- What to do
- Affects up to 11.0.5. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Sep 25, 2026ITFlow before 26.08 allows SVG attachments in the ticket email parser (cron/ticket_email_parser.php) for email messages that may arrive over SMTP from arbitraryCVE-2026-97735 · Other software · ITFlow · reported by MITREHigh 8
ITFlow before 26.08 allows SVG attachments in the ticket email parser (cron/ticket_email_parser.php) for email messages that may arrive over SMTP from arbitrary senders.
- Product
- ITFlow
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 19, 2026Exim before 4.100.1 allows SMTP smuggling in which the received message does not match any sent message, and instead depends on crafted data sent after a rejectCVE-2026-94057 · Other software · Exim · reported by MITREMedium 4
Exim before 4.100.1 allows SMTP smuggling in which the received message does not match any sent message, and instead depends on crafted data sent after a rejection during DATA processing.
- Product
- Exim
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 18, 2026A flaw was found in Netty netty-codec-smtp.CVE-2026-93576 · Other software · Red Hat · reported by Red HatHigh 7.5
A flaw was found in Netty netty-codec-smtp. The component does not properly validate Carriage Return (CR) and Line Feed (LF) characters in the SMTP command-name field. A remote attacker, if an application routes untrusted input into this field, can embed CR/LF characters to inject arbitrary SMTP commands. This can lead to SMTP command smuggling, allowing for unauthorized email relay or spoofing of sender/recipient addresses. While the impact is significant, the real-world exploitability is considered lower as applications typically do not place user-controlled data in the command-name field.
- Product
- Red Hat build of Apache Camel for Spring Boot 4
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordaccess.redhat.combugzilla.redhat.com
Sep 18, 2026A flaw was found in Netty's `SmtpResponseDecoder` component.CVE-2026-93563 · Other software · Red Hat · reported by Red HatHigh 7.5
A flaw was found in Netty's `SmtpResponseDecoder` component. A remote attacker, acting as a malicious or man-in-the-middle (MITM) SMTP server, could exploit this by sending a specially crafted, unbounded multi-line SMTP response without a terminator. This vulnerability leads to unbounded memory accumulation within the client's Java Virtual Machine (JVM) heap, causing an `OutOfMemoryError` and a denial of service (DoS) due to a process crash.
- Product
- Red Hat build of Apache Camel for Spring Boot 4
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordaccess.redhat.combugzilla.redhat.com
Sep 13, 2026N-able Mail Assure through April 2026 contains a design-level authorization flaw that allows an authenticated SMTP user to send outbound email using MAIL FROM aCVE-2025-68624 · Other software · N-able · reported by MITREMedium 4.3
N-able Mail Assure through April 2026 contains a design-level authorization flaw that allows an authenticated SMTP user to send outbound email using MAIL FROM addresses belonging to other tenants. When connecting to the SMTP TCP port and performing SMTP AUTH with valid credentials, the server accepts arbitrary sender domains without enforcing any domain-to-account binding. As a result, an attacker from any tenant can impersonate other tenant domains, producing messages that pass SPF and DMARC validation. NOTE: N-able's position is that the behavior is intended functionality of its shared SMTP relay architecture and that the service does not represent that it enforces per-tenant sender-domain binding.
- Product
- Mail Assure
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddeepsec.netgist.github.com
Sep 11, 2026aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TOCVE-2026-90467 · Other software · cole · reported by VulnCheckMedium 6.3
aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TO command lines. Attackers can craft malicious addresses containing spaces and angle brackets to append parameters like AUTH, NOTIFY, or ORCPT to envelope commands, forging authenticated identities or forcing delivery notifications to third parties.
- Product
- aiosmtplib
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 31, 2026Post SMTP: Missing AuthorizationCVE-2026-81278 · WordPress plugins & themes · reported by PatchstackMedium 5.4
Missing Authorization vulnerability in WPExperts Post SMTP allows Exploiting Incorrectly Configured Access Control Security Levels. This issue affects Post SMTP: from 4.0.0 through beta.1.
- Product
- Post SMTP
- What to do
- Update Post SMTP to the newest version.
Aug 31, 2026Nodemailer before 8.0.4 is vulnerable to SMTP command injection through the unsanitized envelope.size parameter.CVE-2026-82854 · Other software · nodemailer · reported by VulnCheckCritical 9.3
Nodemailer before 8.0.4 is vulnerable to SMTP command injection through the unsanitized envelope.size parameter. When an application passes a custom envelope object with a size property containing CRLF characters to sendMail(), the value is concatenated into the SMTP MAIL FROM command (as SIZE=...) without sanitization, allowing injection of arbitrary SMTP commands such as RCPT TO to silently add attacker-controlled recipients. Exploitation requires the application to expose the envelope size to attacker-controlled input, as Nodemailer does not include size in the default auto-constructed envelope.
- Product
- nodemailer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Aug 31, 2026Nodemailer versions before 8.0.5 contain an SMTP command injection vulnerability in the transport name option used in EHLO/HELO commands.CVE-2026-82853 · Other software · nodemailer · reported by VulnCheckMedium 6.9
Nodemailer versions before 8.0.5 contain an SMTP command injection vulnerability in the transport name option used in EHLO/HELO commands. The name parameter is concatenated directly into SMTP commands without sanitizing carriage return and line feed characters, allowing attackers to inject arbitrary SMTP commands for email spoofing and phishing attacks.
- Product
- nodemailer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Aug 20, 2026aiosmtplib is an asynchronous SMTP client for use with asyncio.CVE-2026-55558 · Other software · cole · reported by GitHubMedium 5.9
aiosmtplib is an asynchronous SMTP client for use with asyncio. Prior to 5.1.2, SMTPProtocol.start_tls in src/aiosmtplib/protocol.py consumes the server's 220 response and starts the TLS handshake without clearing SMTPProtocol._buffer. An active network attacker can place attacker-chosen SMTP response lines after the plaintext 220 response in the same network segment. The method then calls loop.start_tls; those bytes survive the transport upgrade and are parsed as the first response from inside the TLS session, desynchronizing subsequent SMTP command and response pairs. Connections using start_tls=True or opportunistic STARTTLS are affected, while connections using use_tls=True are not. This issue is fixed in version 5.1.2.
- Product
- aiosmtplib
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 20, 2026Unauthenticated Cross Site Scripting (XSS) in SmartSMTP <= 1.2.0 versions.CVE-2026-66606 · WordPress plugins & themes · reported by PatchstackHigh 7.1
Unauthenticated Cross Site Scripting (XSS) in SmartSMTP <= 1.2.0 versions.
- Affected
- up to 1.2.0
- What to do
- Affects up to 1.2.0. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Aug 18, 2026aiosmtplib is an asynchronous SMTP client for use with asyncio.CVE-2026-53533 · Other software · cole · reported by GitHubMedium 6.9
aiosmtplib is an asynchronous SMTP client for use with asyncio. Prior to 5.1.1, SMTP.mail(), SMTP.rcpt(), SMTP.vrfy(), and SMTP.expn() send caller-supplied addresses without rejecting embedded CR or LF bytes. Data after the line break is framed as additional standalone SMTP command lines, allowing an attacker who influences an envelope sender or recipient to inject commands such as MAIL FROM, RCPT TO, RSET, DATA, or AUTH. SMTP.sendmail() and SMTP.send() without a Message object pass addresses through the affected methods, while SMTP.send_message() is not affected. Successful injection can desynchronize the command-response pipeline, hang the SMTP instance, or send an arbitrary message without requiring attacker control of the SMTP server. This issue is fixed in version 5.1.1.
- Product
- aiosmtplib
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Subscriber Cross Site Scripting (XSS) in AcyMailing SMTP Newsletter <= 10.11.1 versions.CVE-2026-28182 · WordPress plugins & themes · reported by PatchstackMedium 6.5
Subscriber Cross Site Scripting (XSS) in AcyMailing SMTP Newsletter <= 10.11.1 versions.
- Affected
- up to 10.11.1
- What to do
- Affects up to 10.11.1. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Aug 13, 2026Subscriber Broken Access Control in AcyMailing SMTP Newsletter <= 10.11.1 versions.CVE-2026-28181 · WordPress plugins & themes · reported by PatchstackMedium 6.5
Subscriber Broken Access Control in AcyMailing SMTP Newsletter <= 10.11.1 versions.
- Affected
- up to 10.11.1
- What to do
- Affects up to 10.11.1. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Aug 6, 2026FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider: Stored Cross-Site ScriptingCVE-2026-16636 · WordPress plugins & themes · reported by WordfenceHigh 7.2
The FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Recipient Display Name (to.name) in Email Logs in all versions up to, and including, 2.2.95 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload is delivered via an attacker-controlled recipient display name (to.name) in a wp_mail() call and does not fire in the log list view — only in the detail view when an administrator uses the Prev/Next navigation controls, as that path bypasses the escapeHtml pipeline used by the list view.
- Product
- FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider
- Affected
- up to 2.2.95
- What to do
- Affects up to 2.2.95. Update FluentSMTP – WP SMTP Plugin with Amazon SES, SendGrid, MailGun, Postmark, Google and Any SMTP Provider to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Full record and what to do →NVD recordplugins.trac.wordpress.orgplugins.trac.wordpress.org
Jul 28, 2026SuperPlane before 0.30.0 contains an SMTP header injection vulnerability that allows unauthenticated attackers to inject arbitrary SMTP headers by including CRLCVE-2026-57511 · Other software · superplanehq · reported by VulnCheckMedium 6.3
SuperPlane before 0.30.0 contains an SMTP header injection vulnerability that allows unauthenticated attackers to inject arbitrary SMTP headers by including CRLF sequences in the event payload title field delivered via webhook. Attackers can manipulate the unsanitized title field passed to the SMTP DATA command to add Bcc recipients for content exfiltration, forge the From address to bypass SPF and DKIM checks, or inject Content-Type and MIME boundary headers to corrupt message bodies for phishing.
- Product
- superplane
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 23, 2026GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the General Settings SMTP configuration that allows authenticated attackers toCVE-2026-48536 · Other software · GFI Software · reported by VulnCheckMedium 5.1
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the General Settings SMTP configuration that allows authenticated attackers to inject arbitrary web script or HTML via the SMTP server address parameter to /Archiver/GeneralSettingsWizard.aspx. The injected payload is stored by GeneralSettingsWizard.SaveAllConfigSettings() without output encoding and is executed in the browsers of users who subsequently view the General Settings page.
- Product
- GFI Archiver
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 21, 2026SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover.CVE-2026-28313 · Other software · SolarWinds · reported by psirt@solarwinds.comCritical 9.1
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover. The impact is lower in Windows deployments.
- Product
- Serv-U
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocumentation.solarwinds.comhttps
Jul 13, 2026AcyMailing SMTP Newsletter: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')CVE-2026-57741 · WordPress plugins & themes · reported by PatchstackHigh 7.1
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in AcyMailing Newsletter Team AcyMailing SMTP Newsletter acymailing allows Stored XSS.This issue affects AcyMailing SMTP Newsletter: from n/a through <= 10.11.0.
- Product
- AcyMailing SMTP Newsletter
- Affected
- up to 10.11.0
- What to do
- Affects up to 10.11.0. Update AcyMailing SMTP Newsletter to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Jul 13, 2026AcyMailing SMTP Newsletter: Missing AuthorizationCVE-2026-57740 · WordPress plugins & themes · reported by PatchstackHigh 7.1
Missing Authorization vulnerability in AcyMailing Newsletter Team AcyMailing SMTP Newsletter acymailing allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects AcyMailing SMTP Newsletter: from n/a through <= 10.11.1.
- Product
- AcyMailing SMTP Newsletter
- Affected
- up to 10.11.1
- What to do
- Affects up to 10.11.1. Update AcyMailing SMTP Newsletter to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Jul 13, 2026AcyMailing SMTP Newsletter: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')CVE-2026-57739 · WordPress plugins & themes · reported by PatchstackCritical 9.3
Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in AcyMailing Newsletter Team AcyMailing SMTP Newsletter acymailing allows Blind SQL Injection.This issue affects AcyMailing SMTP Newsletter: from n/a through <= 10.11.0.
- Product
- AcyMailing SMTP Newsletter
- Affected
- up to 10.11.0
- What to do
- Affects up to 10.11.0. Update AcyMailing SMTP Newsletter to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Jul 10, 2026Newsletter, SMTP, Email marketing and Subscribe forms by Brevo (formely Sendinblue): Reflected Cross-Site ScriptingCVE-2026-15297 · WordPress plugins & themes · reported by WordfenceMedium 6.1
The Newsletter, SMTP, Email marketing and Subscribe forms by Brevo (formely Sendinblue) plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the page parameter in all versions up to, and including, 3.1.77 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
- Product
- Newsletter, SMTP, Email marketing and Subscribe forms by Brevo (formely Sendinblue)
- Affected
- up to 3.1.77
- What to do
- Affects up to 3.1.77. Update Newsletter, SMTP, Email marketing and Subscribe forms by Brevo (formely Sendinblue) to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Full record and what to do →NVD recordplugins.trac.wordpress.orgplugins.trac.wordpress.org
Jun 26, 2026Unauthenticated Cross Site Request Forgery (CSRF) in Gmail SMTP <= 1.2.3.19 versions.CVE-2026-57657 · WordPress plugins & themes · reported by PatchstackMedium 4.3
Unauthenticated Cross Site Request Forgery (CSRF) in Gmail SMTP <= 1.2.3.19 versions.
- What to do
- Update the plugin to the newest version.
Jun 25, 2026Hydra through 9.7, fixed in commit 9cc84c2, contains a stack buffer overflow in NTLM authentication across SMTP, POP3, IMAP, NNTP, HTTP, HTTP-Proxy, and HTTP-PrCVE-2026-56766 · Other software · vanhauser-thc · reported by VulnCheckHigh 8.6
Hydra through 9.7, fixed in commit 9cc84c2, contains a stack buffer overflow in NTLM authentication across SMTP, POP3, IMAP, NNTP, HTTP, HTTP-Proxy, and HTTP-Proxy-Urlenum modules when processing malicious NTLM Type-2 challenges. A malicious server can send a crafted NTLM Type-2 challenge with an excessively long domain string, causing base64-encoded response data to overflow a 500-byte stack buffer by 18 to 330 bytes, enabling remote code execution on systems without stack protection.
- Product
- thc-hydra
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Jun 15, 2026Unauthenticated Cross Site Scripting (XSS) in Post SMTP <= 3.6.2 versions.CVE-2026-48838 · WordPress plugins & themes · reported by PatchstackHigh 7.1
Unauthenticated Cross Site Scripting (XSS) in Post SMTP <= 3.6.2 versions.
- Affected
- up to 3.6.2
- What to do
- Affects up to 3.6.2. Update the plugin to the newest version and check its changelog mentions this fix; if there isn’t one yet, deactivate it until there is.
Jun 4, 2026There is a vulnerability in the Supermicro BMC SMTP service at Supermicro AS-2115HS-TNR.CVE-2026-3820 · Other software · SMCI · reported by def9a96e-e099-41a9-bfac-30fd4f82c411High 7.2
There is a vulnerability in the Supermicro BMC SMTP service at Supermicro AS-2115HS-TNR. An attacker may obtain administrator privileges and inject specially crafted characters into the SMTP service configuration. This may cause the underlying system to execute unintended commands during process invocation. Potential impact includes denial-of-service attacks, arbitrary code execution, or permanent compromise of the controller.
- Product
- AS-2115HS-TNR
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 4, 2026System log files output unencrypted SMTP server authentication passwords alongside sensitive employee corporate identification data.CVE-2026-50205 · Other software · Acer · reported by 8fc372e3-d9c5-46e4-9410-38469745c639High 8.8
System log files output unencrypted SMTP server authentication passwords alongside sensitive employee corporate identification data.
- Product
- Connect M6E 5G Portable WiFi Router
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 1, 2026Apache Airflow's EmailOperator and the underlying `airflow.utils.email` helpers established SMTP STARTTLS connections without verifying the remote certificate wCVE-2026-49267 · Websites & servers · Apache Software Foundation · reported by security@apache.orgMedium 5.9
Apache Airflow's EmailOperator and the underlying `airflow.utils.email` helpers established SMTP STARTTLS connections without verifying the remote certificate when the deployment used `[email] smtp_starttls=True` without `[email] smtp_ssl`. An attacker positioned between the worker and the configured SMTP server (network MITM — typical hostile-network attack-surface for environments where the SMTP relay sits outside the worker's trust boundary) could present a self-signed certificate, have the worker complete the STARTTLS handshake silently, and capture the SMTP AUTH credentials and message contents the worker forwarded. This CVE covers the **core apache-airflow side** of the same root cause already covered for the SMTP provider by `CVE-2026-41016` (published 2026-04-27, covering `apache-airflow-providers-smtp`). Users who already applied the SMTP-provider fix from CVE-2026-41016 should additionally upgrade `apache-airflow` to 3.2.2 or later to cover the core-side path through `airflow.utils.email`. Affects deployments configured with `smtp_starttls=True` and `smtp_ssl=False` where the SMTP relay is reachable across a less-trusted network segment than the worker. Users are advise
- Product
- Apache Airflow
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comlists.apache.org
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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