GHSA-p538-c434-8v24 is a medium-severity (CVSS 5.4) CWE-88 vulnerability in gitpython. A fix is available for gitpython — see the affected versions and patch details below.
GitPython: Arbitrary file truncation via git rev-list --output argument injection in unguarded Commit.count
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-p538-c434-8v24.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-p538-c434-8v24 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
gitpythonReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Commit.count() forwards **kwargs into rev_list with no check_unsafe_options guard (the guard exists only in the sibling iter_items, commit.py:341). git rev-list --output=<path> opens and truncates the target file to 0 bytes before revision parsing, so count(output='/victim') destroys/blanks an arbitrary file.
Root Cause
commit.py:290-291 calls self.repo.git.rev_list(self.hexsha, **kwargs) with no check_unsafe_options and no allow_unsafe_options parameter. The sibling iter_items (commit.py:341) is guarded; count is not. This is a distinct, uncovered sink — GHSA-956x-8gvw-wg5v fixed iter_commits/blame, not count.
Impact
Destroy/blank an arbitrary file at process privilege (integrity/availability). Reachability is key-control only (count uses self.hexsha, not a user ref), and the write is a 0-byte truncation (no content control), so MEDIUM.
Proof of Concept
commit.count(output='/path/to/victim') # victim truncated to 0 bytes (verified)
# control: commit.iter_commits(output=...) raises UnsafeOptionError
Attack Chain
- Entry: app forwards user options ->
commit.count(output='/victim'). Guard: none. Bypass proof:iter_commits(output=)raises UnsafeOptionError;count(output=)does not — verified side-by-side. - Sink:
git rev-list <sha> --output=/victim-> file truncated to 0 bytes. Impact: destroy/blank arbitrary file.
Bypass Evidence
Live-verified on HEAD (tag 3.1.53): count(output=<victim>) truncated a pre-existing file to 0 bytes; guarded iter_commits(output=) raised UnsafeOptionError. Same CNA-accepted "app forwards user options dict" model as GHSA-956x-8gvw-wg5v's archive(**kwargs). Uncovered sink, not a duplicate.
Affected Versions
<= 3.1.53
Suggested Fix
Add check_unsafe_options to Commit.count (mirroring iter_items).
Reported by zx (Jace) — GitHub: @manus-use
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | gitpython | all versions | 3.1.56pip install --upgrade 'gitpython==3.1.56' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for gitpython, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update gitpython to 3.1.56 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-p538-c434-8v24 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-p538-c434-8v24 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-p538-c434-8v24. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-p538-c434-8v24 in your dependencies?
O3 Security finds GHSA-p538-c434-8v24 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.