CVE-2026-4603
MEDIUM5.9EPSS 0.01%jsrsasign: Division by Zero Allows Invalid JWK Modulus to Cause Deterministic Zero Output in RSA Operations
Published: 3/23/2026Modified: 3/30/2026
Also known as:GHSA-464q-cqxq-xhgr
Description
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 (1)
- npm/jsrsasignfrom 0, < 11.1.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P |
| osv | CVSS 3.1 | MEDIUM5.9 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
References (6)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-4603
- PATCHhttps://github.com/kjur/jsrsasign
- WEBhttps://gist.github.com/Kr0emer/5366b7364c4fbf7e754bc377f321e9f3
- WEBhttps://github.com/kjur/jsrsasign/commit/dc41d49fac4297e7a737a3ef8ebd0aa9c49ef93f
- WEBhttps://github.com/kjur/jsrsasign/pull/649
- WEBhttps://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371176