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CVE-2026-24001 kpdecker CVE debrief

CVE-2026-24001 is a denial of service vulnerability in jsdiff, a JavaScript text differencing implementation. The vulnerability allows an attacker to cause a DoS attack by parsing a patch with malicious filename headers containing line break characters. This can cause the parsePatch method to enter an infinite loop, consuming memory until the process crashes. The vulnerability affects versions prior to 8.0.3, 5.2.2, 4.0.4, and 3.5.1. A large payload is not needed to trigger the vulnerability, making size limits on user input ineffective. Some applications may be vulnerable even when calling parsePatch on a patch generated by the application itself if the user can control the filename headers.

Vendor
kpdecker
Product
jsdiff
CVSS
LOW 2.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-01-22
Original CVE updated
2026-06-30
Advisory published
2026-01-22
Advisory updated
2026-06-30

Who should care

Developers and administrators using jsdiff in their applications should be aware of this vulnerability and take steps to mitigate it. This includes updating to a patched version of jsdiff and being cautious when parsing user-provided patches. Additionally, users of applications that rely on jsdiff should be aware of the potential for DoS attacks and monitor their applications for suspicious activity.

Technical summary

The vulnerability is caused by the parsePatch method's inability to handle filename headers containing line break characters. This can cause the method to enter an infinite loop, consuming memory until the process crashes. The vulnerability can be exploited by parsing a patch with malicious filename headers. The applyPatch method is also affected if called with a string representation of a patch as an argument. A second and lesser interdependent bug, a ReDOS, also exhibits when those same line break characters are present in a patch's patch header.

Defensive priority

High priority should be given to updating to a patched version of jsdiff. In the meantime, a workaround is to avoid parsing patches that contain the line break characters: , , or .

Recommended defensive actions

  • Update to a patched version of jsdiff (8.0.3, 5.2.2, 4.0.4, or 3.5.1)
  • Avoid parsing patches that contain line break characters: , , or
  • Be cautious when parsing user-provided patches
  • Monitor applications for suspicious activity
  • Consider implementing additional security measures to prevent DoS attacks

Evidence notes

The CVE record and NVD detail provide information on the vulnerability, including its description, CVSS score, and affected versions. The source item URL provides additional information on the vulnerability, including references to patches and issue tracking.

Official resources

This article was generated with AI assistance based on the supplied source corpus.