Description

GitPython versions before 3.1.54 contain an arbitrary file overwrite vulnerability in the Diffable.diff method that fails to validate git options passed through kwargs. Attackers can supply the --output argument via the other parameter or output kwarg to write patch content to attacker-chosen file paths at process privilege level.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.1",
  "pubDate": "2026-08-13T12:17:27.617Z",
  "pubdate": "2026-08-13T12:17:27.617Z",
  "executiveSummary": "An arbitrary file overwrite vulnerability exists in GitPython versions prior to 3.1.54, specifically residing within the Diffable.diff method.\nThe vulnerability stems from insufficient validation of git options passed through keyword arguments or the other parameter.\nAn attacker can exploit this flaw by supplying the --output argument via the affected parameters, allowing them to write arbitrary patch content to attacker-chosen file paths.\nThe impact of successful exploitation includes unauthorized modification or overwriting of critical system files at the operating system process privilege level.\nAffected systems include applications utilizing vulnerable versions of GitPython to process untrusted input or pass unvalidated arguments to underlying git operations.\nThe risk implications are severe, as arbitrary file writes can often lead to further system compromise, privilege escalation, or denial of service depending on the target file paths.\nExploitation requires the attacker to supply malicious input containing specific git configuration parameters to the vulnerable Diffable.diff method.",
  "technicalDetails": "The vulnerability is localized within the Diffable.diff method of the GitPython library, which is responsible for generating diff representations between git objects.\nThe root cause of the vulnerability is the lack of strict input sanitization and validation on git options passed dynamically through keyword arguments (kwargs) and the other parameter.\nGit supports various command-line arguments to modify output behavior, notably the --output flag, which redirects generated patch output to a specified file path on the filesystem.\nBecause GitPython fails to filter or restrict sensitive command-line arguments, an adversary can inject the --output argument through the unvalidated parameters.\nThe step-by-step attack flow begins when an application utilizes the vulnerable Diffable.diff method and processes input supplied or influenced by an untrusted source.\nThe attacker crafts a malicious payload containing the --output argument paired with a target file path of their choice.\nWhen GitPython constructs the underlying git command invocation, it appends the attacker-supplied arguments without appropriate validation.\nThe git binary executes with the process privileges of the running application, interpreting the --output directive and writing the resulting diff patch content directly to the targeted file path.\nThis behavior results in the unintended overwriting or creation of files on the host filesystem.\nThe vulnerable component is the argument handling logic within the Diffable.diff implementation.\nAll GitPython versions prior to 3.1.54 are affected by this vulnerability.\nThe exploitation mechanism operates locally or wherever untrusted data is accepted into the diff generation workflow, executing at the privilege level of the host process."
}