CVE-2026-75803criticalCWE-354

CVE-2026-75803: falha crítica em OpenSSL

AEAD Forgeries with Empty Ciphertext When Using EVP_Cipher()

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28Vexday Risk Score

Sem sinal de exploração. Ela tem alerta oficial do governo brasileiro.

ssvc Trackcvss 9.1epss 0.3%
Alerta oficial no Brasil

O governo federal publicou alerta, recomendação ou boletim que cita esta vulnerabilidade.

Fonte: CTIR Gov (GSI) e CISC Gov.br, sob licença CC BY-ND 3.0.
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Produtos afetados
OpenSSL · OpenSSL