Description
sigstore-java is a sigstore java client for interacting with sigstore infrastructure. Version 2.0.0 erroneously removed verification of the integrated (Rekor entry) time) against the Fulcio certificate. Version 2.1.0 re-added this verification with enhancements that adhere to the Sigstore verification spec. The old sigstore-conformance test for this check was built incorrectly. This vulnerability impacts only users verifying bundles with `dev.sigstore:sigstore-java:2.0.0`. Older versions are not affected; it is fixed in `dev.sigstore:sigstore-java:2.1.0` A malicious actor may exploit this if they were able to access a users system and exfiltrate the temporary private key used during signing and then reuse an old fulcio certificate later without requiring direct access to the user's credentials. Users may protect themselves by re-verifying their artifacts using the newest sigstore-java or another current sigstore client. Transparency logs may also be audited for unauthorized signatures for a suspected reused identity.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| sigstore | sigstore-java | = 2.0.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | golang-github-sigstore-sigstore | No fix yet | — |
| Ubuntu 26.04 LTS | golang-github-sigstore-sigstore | No fix yet | — |
| Ubuntu 24.04 LTS | golang-github-sigstore-sigstore | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | dev.sigstore:sigstore-java | >= 2.0.0, < 2.1.0 | 2.1.0 | GHSA-qqw8-7c2r-jxch |
References
- https://github.com/sigstore/sigstore-java/security/advisories/GHSA-qqw8-7c2r-jxch
- https://github.com/sigstore/sigstore-java/pull/1008
- https://github.com/sigstore/sigstore-java/pull/1185
- https://github.com/sigstore/sigstore-java/commit/4b7a49ebb1813f5b1ff113bcad63246358222d61
- https://github.com/sigstore/sigstore-java/commit/b529335728fc5cfb574161b4b3c06859a8a2aa88