Description
sigstore-js provides JavaScript libraries for interacting with Sigstore services. Prior to 3.2.1, the preAuthEncoding function in @sigstore/core uses Node.js ascii encoding when converting the PAE string to bytes, allowing payloadType to be mutated after signing without invalidating the signature and breaking the type-binding guarantee that DSSE is designed to provide. This issue is fixed in version 3.2.1.
References5
- github.com/sigstore/sigstore-js/commit/b5aa4f1f8d2db0a9dfa6430f…
- github.com/sigstore/sigstore-js/pull/1657
- github.com/sigstore/sigstore-js/releases/tag/%40sigstore%2Fcore…
- github.com/sigstore/sigstore-js/security/advisories/GHSA-jfc7-6…
- github.com/sigstore/sigstore-js/security/advisories/GHSA-jfc7-6…
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L - EPSS — exploit probability
- 0% percentile: 15 · as of 15 November 2026
- CWE
- CWE-347
Could this be exploited in your environment?
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