CVE-2026-73620

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.

Target: gitpython-developers/GitPython Tested: HEAD 07e80555 (2026-07-25), latest release 3.1.55, git version 2.50.1 Reported instances: 2 exploitable, from a sweep of 14 unguarded call sites

Summary

GitPython blocks dangerous git options through Git.check_unsafe_options(), gated per method by an allow_unsafe_options parameter. That guard is applied per call site, so any API that forwards **kwargs into a git command without calling it passes caller-controlled options straight to git.

A mechanical sweep of every method that forwards **kwargs into a .git.<command>(...) call found 14 sites with no guard. Two reach a git option that takes a filesystem path:

| # | Call site | git option | Impact | |---|---|---|---| | 1 | IndexFile.checkout() → git checkout-index | --prefix=<path> | arbitrary file overwrite with repository-controlled content | | 2 | TagReference.create() → git tag | -F <file> / --file=<file> | arbitrary file read, returned in-band |

This is the same defect class already fixed in Commit.count() (GHSA-p538-c434-8v24), Repo.archive() and Git.ls_remote() (GHSA-956x-8gvw-wg5v). Both instances below are still present at HEAD.

Instance 1 — IndexFile.checkout(): arbitrary file overwrite

git/index/base.py:1210 accepts **kwargs and forwards them with no guard:

def checkout(self, paths=None, force=False, fprogress=lambda *args: None, **kwargs):
    ...
    proc = self.repo.git.checkout_index(*args, **kwargs)   # line 1331
    ...
    proc = self.repo.git.checkout_index(args, **kwargs)    # line 1349

There is no allow_unsafe_options parameter and no check_unsafe_options() call in the method.

git checkout-index accepts --prefix=<string>, prepended to every output path. It is not confined to the working tree, so an absolute prefix writes tracked file contents anywhere the process can write, and -f overwrites what is already there.

Reproduction

from git import Repo
Repo("/path/to/repo").index.checkout(prefix="/tmp/target_dir/", a=True, f=True)

Observed (poc/poc_checkout_index.py) — no exception raised, files land outside the repository:

[ALLOWED] no UnsafeOptionError raised
files written outside the repo: ['f.txt']
  f.txt: 'hi\n'

Overwrite of a pre-existing file (poc/poc_ci_overwrite.py) — the victim file held ORIGINAL-DO-NOT-CLOBBER\n before the call:

[ALLOWED] no exception
victim content now: 'hi\n'
OVERWRITTEN: True

Why this rates High

Both halves of the write are attacker-influenced:

• Destination — the prefix kwarg.
• Content — the bytes written are repository blobs, so anyone who can land a file in the repository (a pull-request branch, a mirrored or untrusted repository, an agent-cloned repository) controls exactly what is written.

Commit a file named authorized_keys, .bashrc, config or post-checkout, choose the matching prefix (~/.ssh/, ~/, .git/hooks/), and the write becomes code execution as the service account.

For comparison within this project: GHSA-fjr4-x663-mwxc (arbitrary file overwrite via git diff --output) is rated High, and GHSA-p538-c434-8v24 (arbitrary file truncation via git rev-list --output) is rated Medium. --prefix supplies full content control, so it sits at or above the former.

Instance 2 — TagReference.create(): arbitrary file read

git/refs/tag.py:88 forwards **kwargs into git tag with no guard, and the signature advertises the passthrough:

def create(cls, repo, path, reference="HEAD", logmsg=None, force=False, **kwargs):
    """...
    :param kwargs:
        Additional keyword arguments to be passed to :manpage:`git-tag(1)`.
    """

git tag accepts -F <file> / --file=<file>, which reads the tag message from an arbitrary path. The annotated tag object stores that content and GitPython returns it to the caller via TagReference.tag.message, so the…

GitPython is a python library used to interact with git repositories, high-level like git-porcelain, or low-level like git-plumbing.

Security Fix(es):

GitPython before 3.1.57 contains an incomplete denylist in the unsafe_git_archive_options guard that omits --add-file and --add-virtual-file options. Attackers can supply these options to Repo.archive() to read arbitrary files from the filesystem and include them in the returned archive.(CVE-2026-73619)

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.(CVE-2026-73620)

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).(CVE-2026-73621)

GitPython before 3.1.55 fails to disable environment variable expansion in Remote.create() and Submodule.add() URL handling, allowing attackers to exfiltrate secrets by supplying URLs containing variable references. Attackers can craft URLs with environment variable tokens that are expanded into .git/config and .gitmodules, then transmitted to attacker-controlled hosts during fetch or pull operations.(CVE-2026-73622)

GitPython before 3.1.54 contains an incomplete denylist in unsafe_git_clone_options that omits --template, allowing attackers to achieve arbitrary command execution during clone operations. Attackers can supply --template pointing to a directory containing malicious post-checkout hooks that execute when git clones the repository.(CVE-2026-73623)

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.(CVE-2026-73624)

GitPython versions before 3.1.54 contain a remote code execution vulnerability in the check_unsafe_options guard that can be bypassed by smuggling git options inside single-character kwarg values. Attackers can supply crafted option dictionaries to clone_from, fetch, pull, push, ls_remote, iter_commits, blame, or archive methods to execute arbitrary OS commands via the --upload-pack parameter.(CVE-2026-73625)

GitPython versions before 3.1.58 fail to validate options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout(). Attackers can supply --pathspec-from-file and --pathspec-file-nul parameters to read arbitrary files accessible to the process, with full file contents returned in GitCommandError.stderr.(CVE-2026-76217)

GitPython before 3.1.58 contains a remote code execution vulnerability in Repo.init that forwards unsafe git options without validation. Attackers can supply a template parameter pointing to a directory with malicious git hooks that execute arbitrary code when git operations are performed on the initialized repository.(CVE-2026-76218)

GitPython versions before 3.1.58 contain an arbitrary file overwrite vulnerability in IndexFile.from_tree, IndexFile.reset, and IndexFile.merge_tree methods that append caller-influenced treeish strings to git read-tree without option validation or argument separation. Attackers can inject the --index-output option to…

GitPython is a python library used to interact with git repositories, high-level like git-porcelain, or low-level like git-plumbing.

Security Fix(es):

GitPython before 3.1.57 contains an incomplete denylist in the unsafe_git_archive_options guard that omits --add-file and --add-virtual-file options. Attackers can supply these options to Repo.archive() to read arbitrary files from the filesystem and include them in the returned archive.(CVE-2026-73619)

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.(CVE-2026-73620)

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).(CVE-2026-73621)

GitPython before 3.1.55 fails to disable environment variable expansion in Remote.create() and Submodule.add() URL handling, allowing attackers to exfiltrate secrets by supplying URLs containing variable references. Attackers can craft URLs with environment variable tokens that are expanded into .git/config and .gitmodules, then transmitted to attacker-controlled hosts during fetch or pull operations.(CVE-2026-73622)

GitPython before 3.1.54 contains an incomplete denylist in unsafe_git_clone_options that omits --template, allowing attackers to achieve arbitrary command execution during clone operations. Attackers can supply --template pointing to a directory containing malicious post-checkout hooks that execute when git clones the repository.(CVE-2026-73623)

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.(CVE-2026-73624)

GitPython versions before 3.1.54 contain a remote code execution vulnerability in the check_unsafe_options guard that can be bypassed by smuggling git options inside single-character kwarg values. Attackers can supply crafted option dictionaries to clone_from, fetch, pull, push, ls_remote, iter_commits, blame, or archive methods to execute arbitrary OS commands via the --upload-pack parameter.(CVE-2026-73625)

GitPython versions before 3.1.58 fail to validate options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout(). Attackers can supply --pathspec-from-file and --pathspec-file-nul parameters to read arbitrary files accessible to the process, with full file contents returned in GitCommandError.stderr.(CVE-2026-76217)

GitPython before 3.1.58 contains a remote code execution vulnerability in Repo.init that forwards unsafe git options without validation. Attackers can supply a template parameter pointing to a directory with malicious git hooks that execute arbitrary code when git operations are performed on the initialized repository.(CVE-2026-76218)

GitPython versions before 3.1.58 contain an arbitrary file overwrite vulnerability in IndexFile.from_tree, IndexFile.reset, and IndexFile.merge_tree methods that append caller-influenced treeish strings to git read-tree without option validation or argument separation. Attackers can inject the --index-output option to…

GitPython is a python library used to interact with git repositories, high-level like git-porcelain, or low-level like git-plumbing.

Security Fix(es):

GitPython before 3.1.57 contains an incomplete denylist in the unsafe_git_archive_options guard that omits --add-file and --add-virtual-file options. Attackers can supply these options to Repo.archive() to read arbitrary files from the filesystem and include them in the returned archive.(CVE-2026-73619)

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.(CVE-2026-73620)

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).(CVE-2026-73621)

GitPython before 3.1.55 fails to disable environment variable expansion in Remote.create() and Submodule.add() URL handling, allowing attackers to exfiltrate secrets by supplying URLs containing variable references. Attackers can craft URLs with environment variable tokens that are expanded into .git/config and .gitmodules, then transmitted to attacker-controlled hosts during fetch or pull operations.(CVE-2026-73622)

GitPython before 3.1.54 contains an incomplete denylist in unsafe_git_clone_options that omits --template, allowing attackers to achieve arbitrary command execution during clone operations. Attackers can supply --template pointing to a directory containing malicious post-checkout hooks that execute when git clones the repository.(CVE-2026-73623)

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.(CVE-2026-73624)

GitPython versions before 3.1.54 contain a remote code execution vulnerability in the check_unsafe_options guard that can be bypassed by smuggling git options inside single-character kwarg values. Attackers can supply crafted option dictionaries to clone_from, fetch, pull, push, ls_remote, iter_commits, blame, or archive methods to execute arbitrary OS commands via the --upload-pack parameter.(CVE-2026-73625)

GitPython versions before 3.1.58 fail to validate options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout(). Attackers can supply --pathspec-from-file and --pathspec-file-nul parameters to read arbitrary files accessible to the process, with full file contents returned in GitCommandError.stderr.(CVE-2026-76217)

GitPython before 3.1.58 contains a remote code execution vulnerability in Repo.init that forwards unsafe git options without validation. Attackers can supply a template parameter pointing to a directory with malicious git hooks that execute arbitrary code when git operations are performed on the initialized repository.(CVE-2026-76218)

GitPython versions before 3.1.58 contain an arbitrary file overwrite vulnerability in IndexFile.from_tree, IndexFile.reset, and IndexFile.merge_tree methods that append caller-influenced treeish strings to git read-tree without option validation or argument separation. Attackers can inject the --index-output option to…

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.

GitPython before 3.1.57 fails to guard git option forwarding in IndexFile.checkout() and TagReference.create(), allowing attackers to pass unsafe options via kwargs. Attackers can use --prefix to overwrite arbitrary files with repository content or -F to read arbitrary files returned in-band.

TuxCare rebuilt gitpython to address 11 CVEs. Fixed in 3.1.31.post10+tuxcare.

These are all security issues fixed in the python313-GitPython-3.1.59-2.1 package on the GA media of openSUSE Tumbleweed.

This update for python-GitPython fixes the following issues:

• CVE-2026-67322: environment-variable exfiltration in Repo.clone_from() URL via os.path.expandvars() (bsc#1273357).
• CVE-2026-67323: unguarded Git options passed as keyword arguments in Repo.archive() and git.ls_remote() allow for command injection (bsc#1273358).
• CVE-2026-67325: incomplete command injection blocklist fails to account for git's long-option prefix abbreviation feature and allows for bypass (bsc#1273359).
• CVE-2026-67326: failure to validate newline characters in the section parameter of config_writer() can lead to RCE via core.hooksPath (bsc#1273364).
• CVE-2026-69097: failure to properly escape section names in Git config files allows for injection of arbitrary configuration directives through malicious submodule names and can lead to RCE (bsc#1273414).
• CVE-2026-73619: incomplete denylist in the unsafe_git_archive_options guard that omits --add-file and --add- virtual-file options can lead to arbitrary file reads (bsc#1275755).
• CVE-2026-73620: failure to guard Git option forwarding in IndexFile.checkout() and TagReference.create() can lead to arbitrary file reads and writes (bsc#1275756).
• CVE-2026-73621: argument injection in the Commit.count() method allows for destruction/blanking of arbitrary files (bsc#1275757).
• CVE-2026-73622: failure to disable environment variable expansion in Remote.create() and Submodule.add() URL handling allows for secret exfiltration via URLs containing variable references (bsc#1275751).
• CVE-2026-73623: incomplete denylist in unsafe_git_clone_options that omits --template allows for arbitrary command execution (bsc#1275752).
• CVE-2026-73624: Diffable.diff method fails to validate git options passed through kwargs, which can lead to arbitrary file writes (bsc#1275753).
• CVE-2026-73625: check_unsafe_options guard bypass via smuggling of git options inside single-character kwarg values can lead to arbitrary code execution (bsc#1275754).
• CVE-2026-76217: failure to validate options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout() can lead to arbitrary file reads (bsc#1275745).
• CVE-2026-76218: unguarded git option forwarding in Repo.init allows for arbitrary command execution (bsc#1275746).
• CVE-2026-76219: unguarded git read-tree option forwarding in IndexFile.from_tree/reset/merge_tree can lead to arbitrary file overwrites (bsc#1275747).
• CVE-2026-76220: check_unsafe_options guard can be bypassed by combining a single-character kwarg with split_single_char_options=False, which can lead to arbitrary OS command injection (bsc#1275748).
• CVE-2026-76221: config-name injection in the option-name validator can lead to remote code execution (bsc#1275749).
• CVE-2026-76222: failure to validate submodule names from .gitmodules files allows creation of Git repositories at arbitrary filesystem paths outside the intended clone directory (bsc#1275750).
• CVE-2026-78675: failure to disable merge_includes when parsing .gitmodules can lead to discloseure of local file contents when arbitrary file paths are included via [include] directives (bsc#1276434).
• CVE-2026-78676: failure to safely re-serialize multi-line git-config values during write operations can corrupt dormant quoted values into live injected directives (bsc#1276433).
• CVE-2026-78677: omission of --separate-git-dir from unsafe_git_clone_options allows for creation of arbitrary git directories outside the intended clone destination (bsc#1276432).
• CVE-2026-78678: incomplete denylist in the unsafe_git_revision_options guard that omits --contents and -S options allows for reading of arbitrary files when these options to are passed to Repo.blame() (bsc#1276431).
• CVE-2026-78679: positional reference parameter can bypass an unsafe option guard and allows for arbitrary file read via…

Root has patched GHSA-3f7w-8rr8-f37f in the GitPython package for Root:PyPI. Multiple fixed versions available.

This update for python-GitPython fixes the following issues:

• CVE-2026-42215: command injection via Git options bypass (bsc#1264604).
• CVE-2026-42284: unsafe option check validates multi_options before shlex.split transforms it (bsc#1264605).
• CVE-2026-44243: path traversal in GitPython reference APIs allows arbitrary file write and delete outside the repository (bsc#1264606).
• CVE-2026-44244: newline injection in config_writer().set_value() enables RCE via core.hooksPath (bsc#1264608).
• CVE-2026-67322: vulnerable to environment-variable exfiltration in Repo.clone_from() (bsc#1273357).
• CVE-2026-67323: fails to guard against dangerous Git options passed as keyword arguments in Repo.archive() and git.ls_remote() (bsc#1273358).
• CVE-2026-67325: contains an incomplete command injection blocklist that fails to account for git's long-option prefix abbreviation feature (bsc#1273359).
• CVE-2026-67326: fails to validate newline characters in the section parameter of config_writer() (bsc#1273364).
• CVE-2026-69097: fails to properly escape section names in git config files, allowing attackers to inject arbitrary configuration directives through malicious submodule names (bsc#1273414).
• CVE-2026-73619: incomplete denylist in the unsafe_git_archive_options guard that omits --add-file and --add- virtual-file options can lead to arbitrary file reads (bsc#1275755).
• CVE-2026-73620: failure to guard git option forwarding in IndexFile.checkout() and TagReference.create() can lead to arbitrary file reads and writes (bsc#1275756).
• CVE-2026-73621: argument injection in the Commit.count() method allows for destruction/blanking of arbitrary files (bsc#1275757).
• CVE-2026-73622: failure to disable environment variable expansion in Remote.create() and Submodule.add() URL handling allows for secret exfiltration via URLs containing variable references (bsc#1275751).
• CVE-2026-73623: incomplete denylist in unsafe_git_clone_options that omits --template allows for arbitrary command execution (bsc#1275752).
• CVE-2026-73624: Diffable.diff method fails to validate git options passed through kwargs, which can lead to arbitrary file writes (bsc#1275753).
• CVE-2026-73625: check_unsafe_options guard bypass via smuggling of git options inside single-character kwarg values can lead to arbitrary code execution (bsc#1275754).
• CVE-2026-76217: failure to validate options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout() can lead to arbitrary file reads (bsc#1275745).
• CVE-2026-76218: unguarded git option forwarding in Repo.init allows for arbitrary command execution (bsc#1275746).
• CVE-2026-76219: unguarded git read-tree option forwarding in IndexFile.from_tree/reset/merge_tree can lead to arbitrary file overwrites (bsc#1275747).
• CVE-2026-76220: check_unsafe_options guard can be bypassed by combining a single-character kwarg with split_single_char_options=False, which can lead to arbitrary OS command injection (bsc#1275748).
• CVE-2026-76221: config-name injection in the option-name validator can lead to remote code execution (bsc#1275749).
• CVE-2026-76222: failure to validate submodule names from .gitmodules files allows creation of Git repositories at arbitrary filesystem paths outside the intended clone directory (bsc#1275750).
• CVE-2026-78675: fails to disable merge_includes when parsing .gitmodules, allowing attackers to disclose local file content by including arbitrary file paths via [include] directives (bsc#1276434).
• CVE-2026-78676: fails to safely re-serialize multi-line git-config values during write operations, corrupting dormant quoted values into injected directives (bsc#1276433).
• CVE-2026-78677: allowing creation of arbitrary git directories outside the intended clone destination (bsc#1276432).
• CVE-2026-78678: an incomplete denylist in the unsafe_git_revision_options guard that omits --contents…