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
https://cgit.git.savannah.gnu.org/cgit/patch.git/commit/?id=e6d6a4e021660679d7fc9150f981d4920f722313
Published: 2026-07-09
Updated: 2026-07-09
Base Score: 4.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 5.5
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 4.6
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Medium