CVE-2026-33753
Gravedad CVSS v3.1:
MEDIA
Tipo:
CWE-295
Validación incorrecta de certificados
Fecha de publicación:
08/04/2026
Última modificación:
08/04/2026
Descripción
*** Pendiente de traducción *** rfc3161-client is a Python library implementing the Time-Stamp Protocol (TSP) described in RFC 3161. Prior to 1.0.6, an Authorization Bypass vulnerability in rfc3161-client's signature verification allows any attacker to impersonate a trusted TimeStamping Authority (TSA). By exploiting a logic flaw in how the library extracts the leaf certificate from an unordered PKCS#7 bag of certificates, an attacker can append a spoofed certificate matching the target common_name and Extended Key Usage (EKU) requirements. This tricks the library into verifying these authorization rules against the forged certificate while validating the cryptographic signature against an actual trusted TSA (such as FreeTSA), thereby bypassing the intended TSA authorization pinning entirely. This vulnerability is fixed in 1.0.6.
Impacto
Puntuación base 3.x
6.20
Gravedad 3.x
MEDIA