Bug 2450205 (CVE-2026-4603)

Summary: CVE-2026-4603 jsrsasign: jsrsasign: Cryptographic operations impacted by division by zero via malicious JSON Web Key
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
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 division by zero vulnerability by supplying a specially crafted JSON Web Key (JWK) whose modulus decodes to zero. This vulnerability can force RSA public-key operations, such as verification and encryption, to produce deterministic zero outputs. This impacts the reliability and integrity of cryptographic operations and can conceal "invalid key" errors.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-03-23 06:01:46 UTC
Versions of the package jsrsasign before 11.1.1 are vulnerable to Division by zero due to the RSASetPublic/KEYUTIL parsing path in ext/rsa.js and the BigInteger.modPowInt reduction logic in ext/jsbn.js. An attacker can force RSA public-key operations (e.g., verify and encryption) to collapse to deterministic zero outputs and hide “invalid key” errors by supplying a JWK whose modulus decodes to zero.