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 A verifier may verify a credential from a holder as being "not revoked" when in fact, the holder's credential has been revoked.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.
Scores
CVSS v3
6.5
EPSS
0.0012
EPSS Percentile
30.5%
Attack Vector
PHYSICAL
CVSS:3.1/AV:P/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-327
Status
published
Products (3)
crates.io/anoncreds-clsignatures
0crates.io
crates.io/ursa
0crates.io
hyperledger/ursa
0.1.0
Published
Jan 16, 2024
Tracked Since
Feb 18, 2026