CVE-2026-78677: GitPython clone_from() omits --separate-git-dir from denylist

CVE-2026-78677 · Severity: high · CVSS 7.5 · Published 2026-08-25

GitPython's `Repo.clone_from()` and `Repo.clone()` methods accept a `separate_git_dir` parameter that should be blocked as unsafe by default, but it is missing from the denylist. This allows attackers who control clone arguments to create a git repository's metadata directory (containing executable hooks) at any attacker-chosen filesystem path outside the intended destination, potentially corrupting other repositories or enabling arbitrary code execution.

Technologies: Gitpython Project Gitpython, gitpython (PyPI). Vendors: Gitpython Project, PyPI.

Quick answers

Is CVE-2026-78677 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-78677 being exploited in the wild.
How severe is CVE-2026-78677?
High severity, with a CVSS score of 7.5, published 25 August 2026.
Which products and versions are affected?
gitpython (PyPI) ECOSYSTEM:introduced=0,fixed=3.1.59.
Is there a fix for CVE-2026-78677?
Yes. gitpython (PyPI): upgrade to 3.1.59 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-78677 attacked?
It is attacked over the network or with local access, in a software library.
Am I affected by CVE-2026-78677?
Check whether you run Gitpython Project Gitpython or gitpython (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • gitpython (PyPI): upgrade to 3.1.59 or later
    pip install "gitpython>=3.1.59"

Technical details

GitPython's clone methods forward keyword arguments to underlying `git clone` invocations after checking them against a denylist (`Repo.unsafe_git_clone_options`). The `--separate-git-dir` option redirects the entire `.git` metadata directory (including executable hooks) to an arbitrary caller-controlled path, leaving only a gitlink file at the destination. This option is already correctly blocked by `Repo.unsafe_git_init_options` for `Repo.init()` and is documented as unsafe in the `clone_from()` docstring, but it is absent from `unsafe_git_clone_options`. An attacker who can control a `separate_git_dir` kwarg passed to `clone_from()` or `clone()` can create a git directory structure at any path the process has write permission to, potentially overwriting existing repositories or infrastructure and escalating to hook-based RCE. The vulnerability requires the host application to forward untrusted input into the clone method's kwargs without additional validation, which matches the threat model already accepted for other sibling denylist entries like `--template` and `--config`.

Affected products

  • GitPython GitPython <= 3.1.58

Identifiers

  • CVE-2026-78677
  • GHSA-8mcc-hrx5-hvxc
  • PYSEC-2026-3787

Timeline

  • 2026-09-08: disclosed: Public disclosure via GitHub Advisory Database
  • 2026-09-08: patched: Fix available in GitPython 3.1.59

References

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