CVE-2026-4601

Name: CVE-2026-4601
Creator: NVD / NIST
Published: 2026-03-23T06:16:21.893+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.22%

Last modified Jun 22, 2026

CVE-2026-4601 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Versions of the package jsrsasign before 11.1.1 are vulnerable to Missing Cryptographic Step via the KJUR.crypto.DSA.signWithMessageHash process in the DSA signing implementation. An attacker can recover the private key by forcing r or s to be zero, so the library emits an invalid signature without retrying, and then solves for x from the resulting signature.. EPSS estimates a 0.22% chance of exploitation in the next 30 days.

Description

Versions of the package jsrsasign before 11.1.1 are vulnerable to Missing Cryptographic Step via the KJUR.crypto.DSA.signWithMessageHash process in the DSA signing implementation. An attacker can recover the private key by forcing r or s to be zero, so the library emits an invalid signature without retrying, and then solves for x from the resulting signature.

Metrics

CVSS 3.1

9.1/10

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

CVSS 4.0

8.8/10

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:H/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.22%

12.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-325

Affected Software

Vendor	Product	Versions
Kjur	Jsrsasign	< 11.1.1

References

https://gist.github.com/Kr0emer/93789fe6efe5519db9692d4ad1dad586Exploit, Mitigation, Third Party Advisory
https://github.com/kjur/jsrsasign/commit/0710e392ec35de697ce11e4219c988ba2b5fe0ebPatch
https://github.com/kjur/jsrsasign/pull/645Issue Tracking
https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15370941Third Party Advisory

Timeline

Published: Mar 23, 2026
Last Modified: Jun 22, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-4601?

How severe is CVE-2026-4601?

CVE-2026-4601 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.22% probability of exploitation in the next 30 days.

How do I fix CVE-2026-4601?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-4601?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST