CVE-2026-4601

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.

References

https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15370941

https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-15812269

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4601.json

https://github.com/kjur/jsrsasign/pull/645

https://github.com/kjur/jsrsasign/commit/0710e392ec35de697ce11e4219c988ba2b5fe0eb

https://gist.github.com/Kr0emer/93789fe6efe5519db9692d4ad1dad586

https://bugzilla.redhat.com/show_bug.cgi?id=2450209

https://access.redhat.com/security/cve/CVE-2026-4601

https://access.redhat.com/errata/RHSA-2026:6926

https://access.redhat.com/errata/RHSA-2026:6912

https://access.redhat.com/errata/RHSA-2026:6720

https://access.redhat.com/errata/RHSA-2026:6568

https://access.redhat.com/errata/RHSA-2026:19410

https://access.redhat.com/errata/RHSA-2026:19409

https://access.redhat.com/errata/RHSA-2026:19375

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4

EPSS