CVE-2026-4602

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.

Score

CVSS 4.0 8.7 High

Status

Modified - report@snyk.io

Published

2026-03-23

Last modified

2026-09-10

Weaknesses

CWE-681

Affected products

• Jsrsasign (Kjur)
• Migration Toolkit Virtualization (Redhat)
• Quay (Redhat)

References

• https://gist.github.com/Kr0emer/7ecd2be7d17419e4677315ef3758faf5
• https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195
• https://github.com/kjur/jsrsasign/pull/650
• https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-15812274
• https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371175
• https://access.redhat.com/errata/RHSA-2026:19375
• https://access.redhat.com/errata/RHSA-2026:19409
• https://access.redhat.com/errata/RHSA-2026:19410
• https://access.redhat.com/errata/RHSA-2026:6568
• https://access.redhat.com/errata/RHSA-2026:6720
• https://access.redhat.com/errata/RHSA-2026:6912
• https://access.redhat.com/errata/RHSA-2026:6926
• https://access.redhat.com/security/cve/CVE-2026-4602
• https://bugzilla.redhat.com/show_bug.cgi?id=2450206
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4602.json