VulnerabilityAnalyzed

CVE-2026-56288

GNU patch is vulnerable to a NULL pointer dereference when processing a specially crafted unified-diff patch file.

MEDIUM 4.6EPSS 0.17%

Does this matter?

Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.

Description

GNU patch is vulnerable to a NULL pointer dereference when processing a specially crafted unified-diff patch file. Improper handling of consecutive end-of-file newline markers can corrupt internal hunk (single block of changes in diff) data structures, causing the application to pass a NULL pointer to fwrite() during patch processing. An attacker can trigger this condition with a malicious patch file, causing the utility to crash and resulting in a denial of service. This issue has been fixed in the commit e6d6a4e021660679d7fc9150f981d4920f722313

CVSS 4.0: 4.6 MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.17% probability · 6th percentile
CISA KEV: Not listed
Weakness: CWE-476
Affected: gnu/patch
Source: cvd@cert.pl

References

https://cert.pl/en/posts/2026/07/CVE-2026-56288Third Party Advisory
https://cgit.git.savannah.gnu.org/cgit/patch.git/Patch, Product
https://cgit.git.savannah.gnu.org/cgit/patch.git/commit/?id=e6d6a4e021660679d7fc9150f981d4920f722313Patch

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.