Описание
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.
A flaw in OpenSSL causes EVP_Cipher() 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.
Отчет
Red Hat rates this as Low since exploitation requires a rare API misuse pattern using EVP_Cipher() with empty ChaCha20-Poly1305 or AES-OCB ciphertexts. Standard TLS implementations and typical EVP_Decrypt* workflows are unaffected, resulting in High Attack Complexity. Bypassing tag verification under these narrow conditions permits limited message forgery (Low Integrity) without exposing secrets (No Confidentiality Impact). Additionally, OpenSSL FIPS modules remain unaffected as they do not include these ciphers.
Меры по смягчению последствий
To mitigate this ensure that all integrity check values present in messages are properly checked in accordance with the protocol specification before they are parsed and used. Applications must rigorously calculate the checksum and explicitly verify that the received integrity value matches the calculated one to prevent malicious data injection.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Ansible Automation Orchestrator 2026 | ansible-automation-platform/automation-orchestrator-backend-rhel9 | Fix deferred | ||
| Confidential Cluster Operator | confidential-clusters-beta/attestation-key-register-rhel9 | Fix deferred | ||
| Confidential Cluster Operator | confidential-clusters-beta/compute-pcrs-rhel9 | Fix deferred | ||
| Confidential Cluster Operator | confidential-clusters-beta/confidential-cluster-operator-bundle | Fix deferred | ||
| Confidential Cluster Operator | confidential-clusters-beta/confidential-cluster-rhel9-operator | Fix deferred | ||
| Confidential Cluster Operator | confidential-clusters-beta/registration-server-rhel9 | Fix deferred | ||
| Confidential Compute Attestation | agent-sandbox/agent-sandbox-router | Fix deferred | ||
| Confidential Compute Attestation | build-of-trustee/trustee-rhel9 | Fix deferred | ||
| Confidential Compute Attestation | openshift-sandboxed-containers/osc-podvm-builder-rhel9 | Fix deferred | ||
| Confidential Compute Attestation | openshift-sandboxed-containers/osc-podvm-payload-rhel9 | Fix deferred |
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Дополнительная информация
Статус:
EPSS
3.7 Low
CVSS3
Связанные уязвимости
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 t...
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
Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ...
EPSS
3.7 Low
CVSS3