Vulnerability in Hyperledger Ursa
CVE-2022-31021
Ursa is a cryptographic library for use with blockchains. A weakness in the Hyperledger AnonCreds specification that is not mitigated in the Ursa and AnonCreds implementations is that the Issuer does not publish a key correctness proof demonstrating that a generated private key is sufficient to meet the unlinkability guarantees of AnonCreds. The Ursa and AnonCreds CL-Signatures implementations always generate a sufficient private key. A malicious issuer could in theory create a custom CL Signature implementation (derived from the Ursa or AnonCreds CL-Signatures implementations) that uses weakened private keys such that presentations from holders could be shared by verifiers to the issuer who could determine the holder to which the credential was issued. This vulnerability could impact holders of AnonCreds credentials implemented using the CL-signature scheme in the Ursa and AnonCreds implementations of CL Signatures. The ursa project has has moved to end-of-life status and no fix is expected.
EPSS: 0.004 (35.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.
Affected products
- Hyperledger Ursa — versions <= 0.3.7
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Exploit, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2022-31021?
- CVE-2022-31021 is a low-severity vulnerability in Hyperledger Ursa, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 3.3/10. Published 2024-01-16.
- How severe is CVE-2022-31021?
- Low severity. CVSS v3 base score is 3.3 out of 10.