CVE-2026-4601: jsrsasign: Missing cryptographic validation during DSA signing enables private key extraction
(updated )
Versions of the package jsrsasign before 11.1.1 are vulnerable to Missing Cryptographic Step via the KJUR.crypto.DSA.signWithMessageHash process in the DSA signing implementation. An attacker can recover the private key by forcing r or s to be zero, so the library emits an invalid signature without retrying, and then solves for x from the resulting signature.
References
- gist.github.com/Kr0emer/93789fe6efe5519db9692d4ad1dad586
- github.com/advisories/GHSA-w8q8-93cx-6h7r
- github.com/kjur/jsrsasign
- github.com/kjur/jsrsasign/commit/0710e392ec35de697ce11e4219c988ba2b5fe0eb
- github.com/kjur/jsrsasign/pull/645
- nvd.nist.gov/vuln/detail/CVE-2026-4601
- security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15370941
Code Behaviors & Features
Detect and mitigate CVE-2026-4601 with GitLab Dependency Scanning
Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →