CVE-2026-4599 — Vulnerability in jsrsasign — CVE Details

CRITICAL

jsrsasign: Incomplete Comparison Allows DSA Private Key Recovery via Biased Nonce Generation

Published March 23, 2026Updated July 21, 2026Source: osv

Summary

Versions of the package jsrsasign from 7.0.0 and before 11.1.1 are vulnerable to Incomplete Comparison with Missing Factors via the getRandomBigIntegerZeroToMax and getRandomBigIntegerMinToMax functions in src/crypto-1.1.js; an attacker can recover the private key by exploiting the incorrect compareTo checks that accept out-of-range candidates and thus bias DSA nonces during signature generation.

Advisory Timeline

First published March 23, 2026 (203 days ago).
Last revised July 21, 2026 — 120 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

npm

Update jsrsasign to 11.1.1 or later

npm install jsrsasign@11.1.1

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: npm (1).

Package	Ecosystem	Affected	Fixed In
jsrsasign	npm	All versions	11.1.1

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-1023
View on MITRE
CWE-338
Use of Cryptographically Weak Pseudo-Random Number GeneratorMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.1 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

Frequently Asked Questions

What is CVE-2026-4599?: jsrsasign: Incomplete Comparison Allows DSA Private Key Recovery via Biased Nonce Generation This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.1/10).
How do I check if my project is affected by CVE-2026-4599?: CVE-2026-4599 affects jsrsasign. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-4599 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

9.1

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-5jx8-q4cp-rhh6

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