CVE-2026-75803

The OpenSSL toolkit is vulnerable to an integrity check failure in the EVP_Cipher() API when used with ChaCha20-Poly1305 and AES-OCB ciphers. Specifically, if an empty ciphertext is provided, the function may report success without verifying the AEAD authentication tag. This flaw allows applicati...

openssl: openssl: AEAD forgeries possible with empty ciphertext in EVP_Cipher()

A flaw in OpenSSL causes EVPCipher to skip AEAD tag verification for ChaCha20-Poly1305 and AES-OCB ciphers when decrypting empty ciphertexts. This allows remote attackers to submit forged messages that affected applications incorrectly accept as valid...

OpenSSL Security Advisory 20260825

OpenSSL Security Advisory 20260825 - 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 EVPCipher function...

AEAD Forgeries with Empty Ciphertext When Using EVP_Cipher()

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 EVPCipher function. Impact summary: Applications calling EVPCipher on an empty ciphertext and...

CVE-2026-75803: Improper Validation of Integrity Check Value

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 EVPCipher function. Impact summary: Applications calling EVPCipher on an empty ciphertext and...

PT-2026-81308

Name of the Vulnerable Software and Affected Versions The product name cannot be determined affected versions not specified Description Decryption using ChaCha20-Poly1305 and AES-OCB ciphers may report success without verifying the authentication tag when an empty ciphertext is processed via the...

An AI Approach to Verified Production Cryptographic Libraries

Cryptographic code is critical infrastructure that must be correct, yet formally verifying production libraries remains difficult. Existing language-model proof systems solve isolated obligations with specifications and premises already given, leaving production-library verification unresolved. W...

CVE-2026-64314 crypto: chacha20poly1305 - validate poly1305 template argument

In the Linux kernel, the following vulnerability has been resolved: crypto: chacha20poly1305 - validate poly1305 template argument chachapolycreate still accepts the compatibility poly1305 parameter in the template name, but it assumes the second template argument is always present and immediatel...

openssl: openssl: AEAD forgeries possible with empty ciphertext in EVP_Cipher()

A flaw in OpenSSL causes EVPCipher to skip AEAD tag verification for ChaCha20-Poly1305 and AES-OCB ciphers when decrypting empty ciphertexts. This allows remote attackers to submit forged messages that affected applications incorrectly accept as valid...

JLSEC-2026-728 In wolfSSL's EVP layer, the ChaCha20-Poly1305 AEAD decryption path in `wolfSSL_EVP_CipherFinal` (and...

In wolfSSL's EVP layer, the ChaCha20-Poly1305 AEAD decryption path in wolfSSLEVPCipherFinal 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,...

Prefix Truncation Attack against ChaCha20-Poly1305 and Encrypt-then-MAC aka Terrapin

SummaryTerrapin is a prefix truncation attack targeting the SSH protocol. More precisely, Terrapin breaks the integrity of SSH's secure channel. By carefully adjusting the sequence numbers during the handshake, an attacker can remove an arbitrary amount of messages sent by the client or server at...

PYSEC-2026-1758 Prefix Truncation Attack against ChaCha20-Poly1305 and Encrypt-then-MAC aka Terrapin

Summary Terrapin is a prefix truncation attack targeting the SSH protocol. More precisely, Terrapin breaks the integrity of SSH's secure channel. By carefully adjusting the sequence numbers during the handshake, an attacker can remove an arbitrary amount of messages sent by the client or server a...

DEBIAN-CVE-2026-13758

CryptX versions before 0.088001 for Perl compare AEAD authentication tags in non-constant time in the streaming decryptdone path. The decryptdone$tag form compares it against the computed tag with memNE memcmp != 0, which short-circuits on the first differing byte, so its run time depends on the...

UBUNTU-CVE-2026-13758

CryptX versions before 0.088001 for Perl compare AEAD authentication tags in non-constant time in the streaming decryptdone path. The decryptdone$tag form compares it against the computed tag with memNE memcmp != 0, which short-circuits on the first differing byte, so its run time depends on the...

CVE-2026-13758

CryptX versions before 0.088001 for Perl compare AEAD authentication tags in non-constant time in the streaming decryptdone path. The decryptdone$tag form compares it against the computed tag with memNE memcmp != 0, which short-circuits on the first differing byte, so its run time depends on the...

GHSA-6VVH-PXR4-25R7 PHP JWT Framework: Chacha20Poly1305 key-encryption algorithm discards the Poly1305 authentication tag, performing no authentication on decryption

Impact The experimental Chacha20Poly1305 key-encryption algorithm generates the 16-byte Poly1305 authentication tag during encryptKey but discards it: the tag is never written to the header and therefore never reaches the wire. On the receiving side, decryptKey calls...

PT-2026-53180

Impact The experimental Chacha20Poly1305 key-encryption algorithm generates the 16-byte Poly1305 authentication tag during encryptKey but discards it: the tag is never written to the header and therefore never reaches the wire. On the receiving side, decryptKey calls openssl...

Updated libssh packages fix security vulnerabilities

CVE-2025-4877 Write beyond bounds in binary to base64 conversion functions CVE-2025-4878 Use of uninitialized variable in privatekeyfromfile CVE-2025-5318 Likely read beyond bounds in sftp server handle management CVE-2025-5351 Double free in functions exporting keys CVE-2025-5372 sshkdf returns ...

Chacha20Poly1305 key-encryption algorithm discards the Poly1305 authentication tag, performing no authentication on decryption

Impact The experimental Chacha20Poly1305 key-encryption algorithm generates the 16-byte Poly1305 authentication tag during encryptKey but discards it: the tag is never written to the header and therefore never reaches the wire. On the receiving side, decryptKey calls...

CVE-2026-41565

CryptX versions before 0.088001 for Perl have a stack buffer overflow in four AEAD decryptverify helpers. The gcmdecryptverify, ccmdecryptverify, chacha20poly1305decryptverify and eaxdecryptverify XS routines copied the caller-supplied authentication tag into a fixed 144-byte stack buffer...