CVE-2023-47122: Gitsign's Rekor public keys fetched from upstream API instead of local TUF client.
Impact
In certain versions of gitsign, Rekor public keys were fetched via the Rekor API, instead of through the local TUF client. If the upstream Rekor server happened to be compromised, gitsign clients could potentially be tricked into trusting incorrect signatures.
There is no known compromise the default public good instance (rekor.sigstore.dev) - anyone using this instance is unlikely to be affected.
Patches
This was fixed in v0.8.0 via https://github.com/sigstore/gitsign/pull/399
Workarounds
n/a
References Are there any links users can visit to find out more?
https://docs.sigstore.dev/about/threat-model/#sigstore-threat-model
Other sources
Gitsign is software for keyless Git signing using Sigstore. In versions of gitsign starting with 0.6.0 and prior to 0.8.0, Rekor public keys were fetched via the Rekor API, instead of through the local TUF client. If the upstream Rekor server happened to be compromised, gitsign clients could potentially be tricked into trusting incorrect signatures. There is no known compromise the default public good instance (rekor.sigstore.dev) - anyone using this instance is unaffected. This issue was fixed in v0.8.0. No known workarounds are available.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the vulnerability ID of this issue?
The vulnerability ID of this issue is CVE-2023-47122.
What is the impact of this vulnerability?
The impact of this vulnerability is that gitsign clients could potentially be tricked into trusting incorrect signatures if the upstream Rekor server is compromised.
What is the severity of CVE-2023-47122?
The severity of CVE-2023-47122 is medium with a CVSS score of 5.3.
How can I fix CVE-2023-47122?
To fix CVE-2023-47122, update gitsign to version 0.8.0 or newer.
Are there any references related to CVE-2023-47122?
Yes, here are some references related to CVE-2023-47122: [Reference 1](https://github.com/sigstore/gitsign/security/advisories/GHSA-xvrc-2wvh-49vc), [Reference 2](https://github.com/sigstore/gitsign/pull/399), [Reference 3](https://github.com/sigstore/gitsign/commit/cd66ccb03c86a3600955f0c15f6bfeb75f697236).