Vulnerability Description
GNU patch is vulnerable to a denial of service (DoS) due to improper validation of hunk (single block of changes in diff) line offsets in unified-diff input. A specially crafted patch can specify an extremely large line number, causing the application to enter an effectively infinite processing loop while attempting to locate the requested position. This results in excessive CPU consumption and prevents the process from completing. An attacker can trigger this behavior by supplying a malicious patch file, causing the utility to become unresponsive and require manual termination. This issue has been fixed in the commit faba04ef4f2b410257f76c1b9dc85e350929c4b9
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Gnu | Patch | <= 2.8.0 |
Related Weaknesses (CWE)
References
- https://cert.pl/en/posts/2026/07/CVE-2026-56288Third Party Advisory
- https://cgit.git.savannah.gnu.org/cgit/patch.git/Patch
- https://cgit.git.savannah.gnu.org/cgit/patch.git/commit/?id=faba04ef4f2b410257f7Patch
FAQ
What is CVE-2026-56289?
CVE-2026-56289 is a vulnerability with a CVSS score of 5.5 (MEDIUM). GNU patch is vulnerable to a denial of service (DoS) due to improper validation of hunk (single block of changes in diff) line offsets in unified-diff input. A specially crafted patch can specify an e...
How severe is CVE-2026-56289?
CVE-2026-56289 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-56289?
Check the references section above for vendor advisories and patch information. Affected products include: Gnu Patch.