Division by zero Affecting jsrsasign package, versions <11.1.1
Threat Intelligence
Exploit Maturity
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
Proof of Concept
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Test your applications- Snyk IDSNYK-JS-JSRSASIGN-15371176
- published22 Mar 2026
- disclosed21 Feb 2026
- creditKr0emer
Introduced: 21 Feb 2026
NewCVE-2026-4603 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade jsrsasign to version 11.1.1 or higher.
Overview
jsrsasign is a free pure JavaScript cryptographic library.
Affected versions of this package 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.