CVE-2024-12797

Issue summary: Clients using RFC7250 Raw Public Keys (RPKs) to authenticate a server may fail to notice that the server was not authenticated, because handshakes don't abort as expected when the SSL_VERIFY_PEER verification mode is set. Impact summary: TLS and DTLS connections using raw public keys may be vulnerable to man-in-middle attacks when server authentication failure is not detected by clients. RPKs are disabled by default in both TLS clients and TLS servers. The issue only arises when TLS clients explicitly enable RPK use by the server, and the server, likewise, enables sending of an RPK instead of an X.509 certificate chain. The affected clients are those that then rely on the handshake to fail when the server's RPK fails to match one of the expected public keys, by setting the verification mode to SSL_VERIFY_PEER. Clients that enable server-side raw public keys can still find out that raw public key verification failed by calling SSL_get_verify_result(), and those that do, and take appropriate action, are not affected. This issue was introduced in the initial implementation of RPK support in OpenSSL 3.2. The FIPS modules in 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue.

Issue summary: Clients using RFC7250 Raw Public Keys (RPKs) to authenticate a server may fail to notice that the server was not authenticated, because handshakes don't abort as expected when the SSL_VERIFY_PEER verification mode is set. Impact summary: TLS and DTLS connections using raw public keys may be vulnerable to man-in-middle attacks when server authentication failure is not detected by clients. RPKs are disabled by default in both TLS clients and TLS servers. The issue only arises when TLS clients explicitly enable RPK use by the server, and the server, likewise, enables sending of an RPK instead of an X.509 certificate chain. The affected clients are those that then rely on the handshake to fail when the server's RPK fails to match one of the expected public keys, by setting the verification mode to SSL_VERIFY_PEER. Clients that enable server-side raw public keys can still find out that raw public key verification failed by calling SSL_get_verify_result(), and those that do, and take appropriate action, are not affected. This issue was introduced in the initial implementation of RPK support in OpenSSL 3.2. The FIPS modules in 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue.

pyca/cryptography's wheels include a statically linked copy of OpenSSL. The versions of OpenSSL included in cryptography 42.0.0-44.0.0 are vulnerable to a security issue. More details about the vulnerability itself can be found in https://openssl-library.org/news/secadv/20250211.txt. If you are building cryptography source ("sdist") then you are responsible for upgrading your copy of OpenSSL. Only users installing from wheels built by the cryptography project (i.e., those distributed on PyPI) need to update their cryptography versions.

pyca/cryptography's wheels include a statically linked copy of OpenSSL. The versions of OpenSSL included in cryptography 42.0.0-44.0.0 are vulnerable to a security issue. More details about the vulnerability itself can be found in https://openssl-library.org/news/secadv/20250211.txt. If you are building cryptography source ("sdist") then you are responsible for upgrading your copy of OpenSSL. Only users installing from wheels built by the cryptography project (i.e., those distributed on PyPI) need to update their cryptography versions.

Resumen del problema: los clientes que utilizan claves públicas sin procesar (RPK) RFC7250 para autenticar un servidor pueden no darse cuenta de que el servidor no se ha autenticado, porque los protocolos de enlace no se cancelan como se espera cuando se establece el modo de verificación SSL_VERIFY_PEER. Resumen del impacto: las conexiones TLS y DTLS que utilizan claves públicas sin procesar pueden ser vulnerables a ataques de intermediarios cuando los clientes no detectan un error de autenticación del servidor. Las RPK están deshabilitadas de forma predeterminada tanto en los clientes TLS como en los servidores TLS. El problema solo surge cuando los clientes TLS habilitan explícitamente el uso de RPK por parte del servidor y el servidor, a su vez, habilita el envío de una RPK en lugar de una cadena de certificados X.509. Los clientes afectados son aquellos que dependen de que el protocolo de enlace falle cuando la RPK del servidor no coincide con una de las claves públicas esperadas, al establecer el modo de verificación en SSL_VERIFY_PEER. Los clientes que habilitan claves públicas sin procesar del lado del servidor aún pueden descubrir que la verificación de clave pública sin procesar falló al llamar a SSL_get_verify_result(), y aquellos que lo hacen y toman las medidas adecuadas no se ven afectados. Este problema se introdujo en la implementación inicial de la compatibilidad con RPK en OpenSSL 3.2. Los módulos FIPS en 3.4, 3.3, 3.2, 3.1 y 3.0 no se ven afectados por este problema.