kjur/jsrsasign · Security
jsrsasign: Missing cryptographic validation during DSA signing enables private key extraction
- GHSA ID
- GHSA-w8q8-93cx-6h7r
- CVE ID
- CVE-2026-4601
- Severity
- high
- Published
- Updated
- CVSS
- 8.7 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
- CVSS v3
- 8.7 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
- CVSS v4
- 8.8 · CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:H/SA:N/E:P
Description
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.
CWEs
- CWE-325 · Missing Cryptographic Step
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-4601 ↗
- https://github.com/kjur/jsrsasign/pull/645 ↗
- https://github.com/kjur/jsrsasign/commit/0710e392ec35de697ce11e4219c988ba2b5fe0eb ↗
- https://gist.github.com/Kr0emer/93789fe6efe5519db9692d4ad1dad586 ↗
- https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15370941 ↗
- https://github.com/advisories/GHSA-w8q8-93cx-6h7r ↗