CVE-2025-52556

Summary

rfc3161-client is a Python library implementing the Time-Stamp Protocol (TSP) described in RFC 3161. Prior to version 1.0.3, there is a flaw in the timestamp response signature verification logic. In particular, chain verification is performed 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. This issue has been patched in version 1.0.3. There is no workaround for this issue.

Affected Software

VendorProductVersion RangeStatus
trailofbitsrfc3161-client< 1.0.3affected

Weaknesses

  • CWE-347: CWE-347: Improper Verification of Cryptographic Signature

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: total

References