CVE-2026-4603

The record

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.

Affected packages

Related vulnerabilities

• GHSA-464q-cqxq-xhgr jsrsasign: Division by Zero Allows Invalid JWK Modulus to Cause Deterministic Zero Output… Same vulnerability
• GHSA-5jx8-q4cp-rhh6 jsrsasign: Incomplete Comparison Allows DSA Private Key Recovery via Biased Nonce… Also affects jsrsasign
• GHSA-8qwj-4jxw-m8jw jsrsasign: Negative Exponent Handling Leads to Signature Verification Bypass Also affects jsrsasign
• GHSA-8g7p-jf3g-gxcp jsrsasign is vulnerable to DoS through Infinite Loop when processing zero or negative… Also affects jsrsasign
• GHSA-wvqx-v3f6-w8rh jsrsasign: DSA signatures or X.509 certificates can be forged via DSA domain-parameter… Also affects jsrsasign
• GHSA-w8q8-93cx-6h7r jsrsasign: Missing cryptographic validation during DSA signing enables private key… Also affects jsrsasign
• CVE-2026-4602 Versions of the package jsrsasign before 11.1.1 are vulnerable to Incorrect Conversion… Also affects jsrsasign
• CVE-2026-4598 Versions of the package jsrsasign before 11.1.1 are vulnerable to Infinite loop via the… Also affects jsrsasign