jsrsasign: Negative Exponent Handling Leads to Signature Verification Bypass

Description

Versions of the package jsrsasign before 11.1.1 are vulnerable to Incorrect Conversion between Numeric Types due to handling negative exponents in ext/jsbn2.js. An attacker can force the computation of incorrect modular inverses and break signature verification by calling modPow with a negative exponent.

Recommendation

Update the jsrsasign package to the latest compatible version. Followings are version details:

• Affected version(s): < 11.1.1
• Patched version(s): 11.1.1

References

• GHSA-8qwj-4jxw-m8jw
• security.snyk.io
• access.redhat.com
• bugzilla.redhat.com
• security.access.redhat.com
• CVE-2026-4602
• CWE-681
• CAPEC-310
• OWASP 2021-A6

Related Issues

• OpenLearnX: Critical Authentication Bypass via JWT Signature Verification Disabled Leading to Account Takeover - CVE-2026-44720
• LiquidJS: memoryLimit Bypass through Negative Range Values Leads to Process Crash - CVE-2026-33285
• OneUptime has authorization bypass via client‑controlled is-multi-tenant-query header that leads to cross‑tenant data ex - CVE-2026-30956
• OneUptime has WhatsApp Resend Verification Authorization Bypass - CVE-2026-30959

You might also like:

Apache and Express Path Traversal plus Nginx Restriction Bypass Tests with SmartScanner

10 Secure Coding Best Practices to Follow in Every Project

Update Cheat Sheet for Developers

Tags:

npm

jsrsasign