CVE-2026-73621 GitPython before 3.1.56 Arbitrary File Truncation via Commit.count

What is CVE-2026-73621?

CVE-2026-73621 is a medium-severity vulnerability in gitpython-developers GitPython, published on 13 Aug 2026.

Official description

GitPython before 3.1.56 contains an argument injection vulnerability in the Commit.count() method, which forwards keyword arguments to 'git rev-list' without the check_unsafe_options guard present in the sibling iter_items method. An attacker who can control options passed to Commit.count (e.g., via an application that forwards a user-supplied options dict) can supply output=<path>, causing 'git rev-list --output=<path>' to open and truncate the target file to zero bytes before revision parsing. This allows destruction/blanking of an arbitrary file at the process's privilege level (no content control, 0-byte truncation).

Weakness: CWE-88

Which versions are affected by CVE-2026-73621?

3 open source packages ship an affected version, including gitpython and GitPython. It affects 1 product.

Products include Gitpython Project Gitpython.

How do I fix CVE-2026-73621?

Upgrade gitpython to 3.1.56 or later.

Is CVE-2026-73621 being exploited?

There is no known exploitation of CVE-2026-73621 in the wild and no public exploit code.

Other vulnerabilities in gitpython-developers GitPython

• CVE-2023-40267 GitPython vulnerable to remote code execution due to insufficient sanitization of input arguments Critical 9.8
• CVE-2026-78676 GitPython before 3.1.59 Remote Code Execution via Config Injection Critical 9.3
• CVE-2026-67324 GitPython 3.1.50 Authentication Bypass via Joined Short Options Critical 9.3
• CVE-2026-42215 GitPython: Command injection via Git options bypass High 8.8
• CVE-2026-87817 GitPython before 3.1.60 Remote Code Execution via Git Directory Impersonation High 8.7

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• GitHub advisory
• How this page is made

Also known as CLSA-2026-1787042950, DEBIAN-CVE-2026-73621, ECHO-7b9b-6ad3-42a3, ECHO-c303-e516-5c89, GHSA-h75v-4jxv-ppxm, GHSA-p538-c434-8v24 and 8 more.