Impact
Metadadata signature verification, as used in tuf.client.updater, counted each of multiple signatures with identical authorized keyids separately towards the threshold. Therefore, an attacker with access to a valid signing key could create multiple valid signatures in order to meet the minimum threshold of keys before the metadata was considered valid.
The tuf maintainers would like to thank Erik MacLean of Analog Devices, Inc. for reporting this issue.
Patches
A fix is available in version 0.12.2 or newer.
Workarounds
No workarounds are known for this issue.
References
- CVE-2020-6174
- Pull request resolving the issue PR 974
References
- https://github.com/theupdateframework/tuf/security/advisories/GHSA-pwqf-9h7j-7mv8
- https://nvd.nist.gov/vuln/detail/CVE-2020-6174
- https://github.com/theupdateframework/tuf/pull/974/commits/a0397c7c820ec1c30ebc793cc9469b61c8d3f50e
- https://github.com/theupdateframework/tuf/pull/974
- https://github.com/advisories/GHSA-pwqf-9h7j-7mv8