Heap-based buffer overflow in libgit2 - #VU138486
Published: July 20, 2026
Vulnerability identifier: #VU138486
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a heap-based buffer overflow in the bundled PCRE 8.45 regex compiler when parsing attacker-controlled revspec patterns through git_revparse_single. A remote attacker can supply a specially crafted revspec pattern to cause a denial of service.
The issue is reachable through revspecs of the form :/<pattern> in configurations using the built-in regex backend.
Affected software
libgit2
Remediation
Install security update from vendor's website.
libgit2 - addressed in versions 1.8.6, 1.9.5