Vulnerability in Sigstore Sigstore-Js
CVE-2026-118763
sigstore-js provides JavaScript libraries for interacting with Sigstore services. Prior to 0.7.2, packages/oci/src/registry.ts contains a RegistryClient.signIn() method that stores registry Authorization and Docker configuration headers as defaults on a shared HTTP client, while RegistryClient.uploadBlob() sends a fresh PUT to an absolute blob-upload Location supplied by the registry without checking that its origin or scheme matches the registry. A malicious or compromised registry can therefore direct a user pushing an artifact through attachArtifactToImage() to an attacker-controlled host and receive the registry bearer token, Basic credentials, or custom authentication headers. Redirect-time header stripping does not prevent the leak because the cross-host PUT is a new explicit request rather than a followed redirect. This is a residual of CVE-2026-59891, whose fix changed credential selection in credentials.ts but did not constrain where credentials are sent from registry.ts. Version 0.7.2 fixes the issue by separating registry credentials from client-wide defaults and sending them only to the registry origin.
Published .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Sigstore Sigstore-Js — versions < 0.7.2
Weakness classification (CWE)
References
- github.com/sigstore/sigstore-js/commit/b855f46cfe81f26481c6d3f4b333dfd00f2fd1b1
- github.com/sigstore/sigstore-js/commit/e4ca65c3ab3c675456ab9b0bd04217ceccad3558
- github.com/sigstore/sigstore-js/pull/1762
- github.com/sigstore/sigstore-js/releases/tag/@sigstore/oci@0.7.2
- github.com/sigstore/sigstore-js/security/advisories/GHSA-j63v-mwhm-56jx
Frequently asked questions
- What is CVE-2026-118763?
- CVE-2026-118763 is a high-severity vulnerability in Sigstore Sigstore-Js, classified under Insufficiently Protected Credentials. CVSS score: 7.4/10. Published 2026-10-29.
- How severe is CVE-2026-118763?
- High severity. CVSS v3 base score is 7.4 out of 10.