Vulnerability · Published Jan 16, 2024 · Assigned by GitHub_M

CVE-2024-21670CL-Signatures Revocation Scheme in Ursa has flaws that allow a holder to demonstrate non-revocation of a revoked credential

Medium 6.5

In plain English

A medium-severity broken cryptography in ursa from hyperledger-archives. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.3%top 79.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Ursa is a cryptographic library for use with blockchains. The revocation schema that is part of the Ursa CL-Signatures implementations has a flaw that could impact the privacy guarantees defined by the AnonCreds verifiable credential model, allowing a malicious holder of a revoked credential to generate a valid Non-Revocation Proof for that credential as part of an AnonCreds presentation. A verifier may verify a credential from a holder as being "not revoked" when in fact, the holder's credential has been revoked. Ursa has moved to end-of-life status and no fix is expected.

Affected products (as reported)

VendorProductVersions
hyperledger-archives ursa <= 0.3.7

Weakness: CWE-327 · Vector: CVSS:3.1/AV:P/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N

References