CVE-2026-33753

Katalog CVE

CVSS 7.5 · High EPSS 0,21%

Kerentanan Improper Certificate Validation pada trailofbits rfc3161-client. Skor CVSS 3.1 7.5 (High) menurut NVD.

Deskripsi (NVD)

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.

Rincian

Terbit di NVD

8 April 2026

Terakhir diubah

24 Juli 2026

Status NVD

Analyzed

CVSS 3.1

7.5 (High), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-295: Improper Certificate Validation

EPSS (30 hari)

0,21% peluang dieksploitasi; lebih tinggi dari 9,7% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/trailofbits/rfc3161-client/security/advisories/GHSA-3xxc-pwj6-jgrj exploit · advisory vendor