CVE-2025-52556 – rfc3161-client

Package

Manager: pip
Name: rfc3161-client
Vulnerable Version: >=0 <1.0.3

Severity

Level: Critical

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00015 pctl0.02149

Details

rfc3161-client has insufficient verification for timestamp response signatures ### Impact `rfc3161-client` 1.0.2 and earlier contain a flaw in their timestamp response signature verification logic. In particular, it performs chain verification against the TSR's embedded certificates up to the trusted root(s), but fails to verify the TSR's own signature against the timestamping leaf certificates. Consequently, vulnerable versions perform insufficient signature validation to properly consider a TSR verified, as the attacker can introduce _any_ TSR signature so long as the embedded leaf chains up to some root TSA. ### Patches Users should immediately upgrade to `rfc3161-client` 1.0.3 or later. ### Workarounds There is no workaround possible. Users should immediately upgrade to a fixed version.

Metadata

Created: 2025-06-20T18:08:40Z
Modified: 2025-06-27T22:02:46Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/06/GHSA-6qhv-4h7r-2g9m/GHSA-6qhv-4h7r-2g9m.json
CWE IDs: ["CWE-347"]
Alternative ID: GHSA-6qhv-4h7r-2g9m
Finding: F204
Auto approve: 1