CVE-2026-4602: High severity npm/jsrsasign vulnerability

Published Mar 23, 2026
·
Updated

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.

Affected Software

2 affected components
npm/jsrsasign<11.1.1
kjur Jsrsasign Node.js<11.1.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade jsrsasign to a version that resolves this vulnerability.

    Fixed in 11.1.1

Event History

Mar 23, 2026
CVE Published
via MITRE·05:00 AM
Data Sourced
via MITRE·05:00 AM
DescriptionSeverityWeakness
Data Sourced
via Red Hat·06:01 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·06:16 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-4602?

CVE-2026-4602 is classified as a high severity vulnerability due to its impact on signature verification.

2

How do I fix CVE-2026-4602?

To fix CVE-2026-4602, upgrade the jsrsasign package to version 11.1.1 or later.

3

Which versions of jsrsasign are affected by CVE-2026-4602?

Versions of the jsrsasign package prior to 11.1.1 are affected by CVE-2026-4602.

4

What kind of attacks can exploit CVE-2026-4602?

CVE-2026-4602 can be exploited by attackers to force incorrect computations of modular inverses, breaching signature verification.

5

Where is CVE-2026-4602 primarily located in the jsrsasign package?

CVE-2026-4602 is primarily found in ext/jsbn2.js within the jsrsasign package.

Contact

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