Vulnerability · Published Jan 22, 2026 · Assigned by GitHub_M
CVE-2026-24001jsdiff has a Denial of Service vulnerability in parsePatch and applyPatch
High 7.5
In plain English
A high-severity uncontrolled resource consumption in jsdiff from kpdecker. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
jsdiff is a JavaScript text differencing implementation. Prior to versions 8.0.3, 5.2.2, 4.0.4, and 3.5.1, attempting to parse a patch whose filename headers contain the line break characters `\r`, `\u2028`, or `\u2029` can cause the `parsePatch` method to enter an infinite loop. It then consumes memory without limit until the process crashes due to running out of memory. Applications are therefore likely to be vulnerable to a denial-of-service attack if they call `parsePatch` with a user-provided patch as input. A large payload is not needed to trigger the vulnerability, so size limits on user input do not provide any protection. Furthermore, some applications may be vulnerable even when calling `parsePatch` on a patch generated by the application itself if the user is nonetheless able to control the filename headers (e.g. by directly providing the filenames of the files to be diffed). The `applyPatch` method is similarly affected if (and only if) called with a string representation of a patch as an argument, since under the hood it parses that string using `parsePatch`. Other methods of the library are unaffected. Finally, a second and lesser interdependent bug - a ReDOS - also exhibits when those same line break characters are present in a patch's *patch* header (also known as its "leading garbage"). A maliciously-crafted patch header of length *n* can take `parsePatch` O(*n*³) time to parse. Versions 8.0.3, 5.2.2, 4.0.4, and 3.5.1 contain a fix. As a workaround, do not attempt to parse patches that contain any of these characters: `\r`, `\u2028`, or `\u2029`.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-diff | no fix listed | DEBIAN-CVE-2026-24001 |
| Debian:13 | node-diff | no fix listed | DEBIAN-CVE-2026-24001 |
| Debian:14 | node-diff | 5.2.2~dfsg+~5.2.3-1 | DEBIAN-CVE-2026-24001 |
| Ubuntu:22.04:LTS | node-diff | no fix listed | UBUNTU-CVE-2026-24001 |
| Ubuntu:24.04:LTS | node-diff | no fix listed | UBUNTU-CVE-2026-24001 |
| Ubuntu:25.10 | node-diff | no fix listed | UBUNTU-CVE-2026-24001 |
| Ubuntu:26.04:LTS | node-diff | no fix listed | UBUNTU-CVE-2026-24001 |
| Ubuntu:26.10 | node-diff | no fix listed | UBUNTU-CVE-2026-24001 |
| npm | diff | 3.5.1 | GHSA-73rr-hh4g-fpgx |
| npm | diff | 4.0.4 | GHSA-73rr-hh4g-fpgx |
| npm | diff | 5.2.2 | GHSA-73rr-hh4g-fpgx |
| npm | diff | 8.0.3 | GHSA-73rr-hh4g-fpgx |
Affected products (as reported)
Weakness: CWE-400, CWE-1333 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/kpdecker/jsdiff/security/advisories/GHSA-73rr-hh4g-fpgx x_refsource_CONFIRM
- https://github.com/kpdecker/jsdiff/issues/653 x_refsource_MISC
- https://github.com/kpdecker/jsdiff/pull/649 x_refsource_MISC
- https://github.com/kpdecker/jsdiff/commit/15a1585230748c8ae6f8274c202e0c87309142f5 x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2026-24001 vdb-entry, x_refsource_REDHAT
- RHBZ#2431930 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-24001.json x_sadp-csaf-vex