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.
12 results
Aug 25, 2026Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success without verifying the supplied authentication tag when the oCVE-2026-75803 · Websites & servers · OpenSSL · reported by openssl-security@openssl.orgCritical 9.1
Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success without verifying the supplied authentication tag when the operation is finalized by calling the EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was passed to the function. The callers of this function might believe that a successful return indicates a valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact: no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms are not FIPS approved and thus not implemented in the FIPS module.
- Product
- OpenSSL
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 25, 2026In the Linux kernel, the following vulnerability has been resolved: crypto: chacha20poly1305 - validate poly1305 template argument chachapoly_create() still aCVE-2026-64314 · Computers, phones & browsers · Linux · reported by 416baaa9-dc9f-4396-8d5f-8c081fb06d67Medium 5.5
In the Linux kernel, the following vulnerability has been resolved: crypto: chacha20poly1305 - validate poly1305 template argument chachapoly_create() still accepts the compatibility poly1305 parameter in the template name, but it assumes the second template argument is always present and immediately passes it to strcmp(). When the argument is missing, crypto_attr_alg_name() returns an error pointer. Check for that before comparing the name so malformed template instantiations fail with an error instead of dereferencing the error pointer in strcmp(). This matches the surrounding Crypto API template pattern where crypto_attr_alg_name() results are validated before string-specific use.
- Product
- Linux
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgit.kernel.orggit.kernel.org
Apr 10, 2026In wolfSSL's EVP layer, the ChaCha20-Poly1305 AEAD decryption path in wolfSSL_EVP_CipherFinal (and related EVP cipher finalization functions) fails to verify thCVE-2026-5479 · Other software · wolfSSL · reported by facts@wolfssl.comHigh 7.6
In wolfSSL's EVP layer, the ChaCha20-Poly1305 AEAD decryption path in wolfSSL_EVP_CipherFinal (and related EVP cipher finalization functions) fails to verify the authentication tag before returning plaintext to the caller. When an application uses the EVP API to perform ChaCha20-Poly1305 decryption, the implementation computes or accepts the tag but does not compare it against the expected value.
- Product
- wolfSSL
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Nov 21, 2025Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt.CVE-2025-11931 · Other software · wolfSSL · reported by facts@wolfssl.comLow 2.1
Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt. This issue is hit specifically with a call to the function wc_XChaCha20Poly1305_Decrypt() which is not used with TLS connections, only from direct calls from an application.
- Product
- wolfSSL
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 22, 2025In the Linux kernel, the following vulnerability has been resolved: s390/crypto: use vector instructions only if available for ChaCha20 Commit 349d03ffd5f6 ("CVE-2023-53702 · Computers, phones & browsers · Linux · reported by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
In the Linux kernel, the following vulnerability has been resolved: s390/crypto: use vector instructions only if available for ChaCha20 Commit 349d03ffd5f6 ("crypto: s390 - add crypto library interface for ChaCha20") added a library interface to the s390 specific ChaCha20 implementation. However no check was added to verify if the required facilities are installed before branching into the assembler code. If compiled into the kernel, this will lead to the following crash, if vector instructions are not available: data exception: 0007 ilc:3 [#1] SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc7+ #11 Hardware name: IBM 3931 A01 704 (KVM/Linux) Krnl PSW : 0704e00180000000 000000001857277a (chacha20_vx+0x32/0x818) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000037f0000000a ffffffffffffff60 000000008184b000 0000000019f5c8e6 0000000000000109 0000037fffb13c58 0000037fffb13c78 0000000019bb1780 0000037fffb13c58 0000000019f5c8e6 000000008184b000 0000000000000109 00000000802d8000 0000000000000109 0000000018571ebc 0000037fffb13718 Krnl Code: 000000001857276a: c07000b1f80b larl %r7,00
- Product
- Linux
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgit.kernel.orggit.kernel.org
Jul 7, 2025A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library.CVE-2025-5987 · Other software · Red Hat · reported by Red HatHigh 8.1
A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenSSL error code returned aliases with the SSH_OK code, resulting in libssh not properly detecting the error returned by the OpenSSL library. This issue can lead to undefined behavior, including compromised data confidentiality and integrity or crashes.
- Product
- Red Hat Enterprise Linux 10
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordaccess.redhat.comaccess.redhat.com
Aug 6, 2024Calling `PK11_Encrypt()` in NSS using CKM_CHACHA20 and the same buffer for input and output can result in plaintext on an Intel Sandy Bridge processor.CVE-2024-7531 · Computers, phones & browsers · Mozilla · reported by security@mozilla.orgMedium 6.5
Calling `PK11_Encrypt()` in NSS using CKM_CHACHA20 and the same buffer for input and output can result in plaintext on an Intel Sandy Bridge processor. In Firefox this only affects the QUIC header protection feature when the connection is using the ChaCha20-Poly1305 cipher suite. The most likely outcome is connection failure, but if the connection persists despite the high packet loss it could be possible for a network observer to identify packets as coming from the same source despite a network path change. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, and Firefox ESR < 128.1.
- Product
- Firefox
- 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
Mar 18, 2024In the CryptX module before 0.062 for Perl, gcm_decrypt_verify() and chacha20poly1305_decrypt_verify() do not verify the tag.CVE-2018-25099 · Other software · dcit · reported by MITRECritical 9.8
In the CryptX module before 0.062 for Perl, gcm_decrypt_verify() and chacha20poly1305_decrypt_verify() do not verify the tag.
- Product
- perl-cryptx
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 27, 2021A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55.CVE-2020-12403 · Computers, phones & browsers · Mozilla · reported by security@mozilla.orgCritical 9.1
A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55. When using multi-part Chacha20, it could cause out-of-bounds reads. This issue was fixed by explicitly disabling multi-part ChaCha20 (which was not functioning correctly) and strictly enforcing tag length. The highest threat from this vulnerability is to confidentiality and system availability.
- Product
- NSS
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordbugzilla.redhat.comdeveloper.mozilla.org
Dec 31, 2020An issue was discovered in the chacha20 crate before 0.2.3 for Rust.CVE-2019-25005 · Other software · Chacha20 Project · reported by MITREHigh 7.5
An issue was discovered in the chacha20 crate before 0.2.3 for Rust. A ChaCha20 counter overflow makes it easier for attackers to determine plaintext.
- Product
- Chacha20
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordrustsec.orgrustsec.org
Mar 6, 2019ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every encryption operation.CVE-2019-1543 · Websites & servers · OpenSSL · reported by openssl-security@openssl.orgHigh 7.4
ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every encryption operation. RFC 7539 specifies that the nonce value (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length and front pads the nonce with 0 bytes if it is less than 12 bytes. However it also incorrectly allows a nonce to be set of up to 16 bytes. In this case only the last 12 bytes are significant and any additional leading bytes are ignored. It is a requirement of using this cipher that nonce values are unique. Messages encrypted using a reused nonce value are susceptible to serious confidentiality and integrity attacks. If an application changes the default nonce length to be longer than 12 bytes and then makes a change to the leading bytes of the nonce expecting the new value to be a new unique nonce then such an application could inadvertently encrypt messages with a reused nonce. Additionally the ignored bytes in a long nonce are not covered by the integrity guarantee of this cipher. Any application that relies on the integrity of these ignored leading bytes of a long nonce may be further affected. Any OpenSSL internal use of this cipher, including in SSL/TLS, is safe b
- Product
- OpenSSL
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordlists.opensuse.orgaccess.redhat.com
May 4, 2017In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads.CVE-2016-7054 · Websites & servers · OpenSSL · reported by openssl-security@openssl.orgHigh 7.5
In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads. This can result in an OpenSSL crash. This issue is not considered to be exploitable beyond a DoS.
- Product
- OpenSSL
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordsecurityfocus.comsecuritytracker.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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