Bug 2450209 (CVE-2026-4601)

Summary: CVE-2026-4601 jsrsasign: jsrsasign: Private Key Recovery via Missing Cryptographic Step in DSA Signing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: bdettelb, doconnor
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in jsrsasign. An attacker can exploit a missing cryptographic step in the Digital Signature Algorithm (DSA) signing process, specifically within the KJUR.crypto.DSA.signWithMessageHash function. By manipulating the signature generation to force specific values, the library emits an invalid signature without retrying. This vulnerability allows an attacker to recover the private key used for signing.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-03-23 06:02:07 UTC
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.