VulnerabilityModified
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.
HIGH 7.7EPSS 0.49%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.49%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 7.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.49% probability · 41th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-681
- Affected
- kjur/jsrsasign
- Source
- report@snyk.io
References
- https://gist.github.com/Kr0emer/7ecd2be7d17419e4677315ef3758faf5Exploit, Mitigation, Third Party Advisory
- https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195Patch
- https://github.com/kjur/jsrsasign/pull/650Issue Tracking
- https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-15812274
- https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371175Third Party Advisory
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.