{"id":"CVE-2026-4602","aliases":["GHSA-8qwj-4jxw-m8jw"],"url":"https://o3.security/vulnerability/CVE-2026-4602","summary":"jsrsasign: Negative Exponent Handling Leads to Signature Verification Bypass","details":"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.","published":"2026-03-23T05:00:10.567Z","modified":"2026-08-04T03:32:25.328531976Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"jsrsasign","fixedVersion":"11.1.1"}],"fix":{"url":"https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195","label":"kjur/jsrsasign@5ea1c32"},"references":[{"type":"WEB","url":"https://gist.github.com/Kr0emer/7ecd2be7d17419e4677315ef3758faf5"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4602.json"},{"type":"WEB","url":"https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-15812274"},{"type":"WEB","url":"https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371175"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19375"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19409"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19410"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6568"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6720"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6912"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6926"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-4602"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/4xxx/CVE-2026-4602.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-4602"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2450206"},{"type":"FIX","url":"https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195"},{"type":"FIX","url":"https://github.com/kjur/jsrsasign/pull/650"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-04T03:32:25.328531976Z"}}