snowflake-cli

## Summary

`IndexFile.remove()` and `Head.checkout()` forward `**kwargs` into `git rm` and `git checkout`
with no guard. Passing `--pathspec-from-file=<file>` **together with `--pathspec-file-nul`**
makes Git treat the whole file as a single NUL-delimited pathspec, and the unmatched-pathspec
error quotes it verbatim. GitPython surfaces that through `GitCommandError.stderr`, so the
entire contents of a caller-chosen file are returned to the caller in band.

This is the same primitive as Instance 2 of
[GHSA-3f7w-8rr8-f37f](https://github.com/advisories/GHSA-3f7w-8rr8-f37f) - `TagReference.create()`
with `-F`, arbitrary file read returned in band - at two sites that advisory assessed and
cleared.

## Prior art, and why I am filing rather than commenting

GHSA-3f7w-8rr8-f37f's sweep table lists these four sites with the assessment
*"`--pathspec-from-file` only reads a pathspec; no write or disclosure primitive found"*:

| Call site | git command | that advisory's assessment |
|---|---|---|
| `IndexFile.remove()` | `rm` | `--pathspec-from-file` only reads a pathspec; no write or disclosure primitive found |
| `IndexFile.move()` | `mv` | same |
| `HEAD.reset()` | `reset` | same |
| `HEAD.checkout()` | `checkout` | same |

That assessment is very nearly right, and I think that is why it held: with
`--pathspec-from-file` alone, Git splits on newlines and the error quotes only the **first
line**, which reads as an uninteresting partial. Adding `--pathspec-file-nul` - a sibling flag
of the same option, and the documented way to handle paths containing newlines - makes the
whole file one pathspec.

## Root cause

`git/index/base.py:991-1043`:

```python
def remove(self, items, working_tree=False, **kwargs):
    ...
    removed_paths = self.repo.git.rm(args, paths, **kwargs).splitlines()   # line 1043
```

`git/refs/head.py:237-268`:

```python
def checkout(self, force: bool = False, **kwargs: Any):
    ...
    self.repo.git.checkout(self, **kwargs)                                 # line 268
```

Neither has an `allow_unsafe_options` parameter or a `check_unsafe_options()` call.

## Proof of concept

```python
from git import Repo
from git.exc import GitCommandError

repo = Repo("/path/to/repo")
kw = dict(pathspec_from_file="/etc/passwd", pathspec_file_nul=True)

try:
    repo.index.remove([], **kw)          # or: repo.heads[0].checkout(**kw)
except GitCommandError as e:
    print(e.stderr)                      # <- entire file contents
```

Observed on published 3.1.57, against a canary file holding three marked lines:

```
[PASS] IndexFile.remove() -> `git rm` returns ALL 3 canary lines in-band
       stderr: 'fatal: pathspec 'LINE1-CANARY-4242
       LINE2-SECRET-7777
       LINE3-TAIL-9999
       ' did not match any files'
[PASS] Head.checkout() -> `git checkout` returns ALL 3 canary lines in-band
       stderr: 'error: pathspec 'LINE1-CANARY-4242
       LINE2-SECRET-7777
       LINE3-TAIL-9999
       ' did not match any file(s) known to git'
[PASS] PRECISION: `git status` leaks 0/3 -- not every unguarded site discloses
[PASS] PRECISION: the GUARDED checkout-index leaks 0/3
```

The two precision controls are there so the result is about these sinks and not about the
canary being visible everywhere.

## Scope correction to the table above

Of the four sites cleared with that sentence, **two disclose and two do not**:

| Call site | disclosed? |
|---|---|
| `IndexFile.remove()` → `git rm` | **yes, full file** |
| `Head.checkout()` → `git checkout` | **yes, full file** |
| `HEAD.reset()` → `git reset` | no - `git reset` does not error on unmatched pathspecs |
| `IndexFile.move()` → `git mv` | no |

The two negatives are mentioned because "the dismissal was wrong" would overstate it: the
dismissal was wrong for half of what it covered.

GitPython: Arbitrary file read via --pathspec-from-file in IndexFile.remove() and Head.checkout() (CVE-2026-76217)

snakemake

GitPython versions prior to 9.25.1 have a vulnerability in the IndexFile.remove() and Head.checkout() methods where passing the --pathspec-from-file option together with --pathspec-file-nul causes Git to treat the entire file as a single NUL-delimited pathspec. When the pathspec does not match any files, Git returns an error message that includes the entire contents of the specified file. This results in an arbitrary file read vulnerability where the contents of a caller-chosen file are exposed via the GitCommandError.stderr output.

shallow-backup

nbdime

GitPython versions from 1.1.0 up to but not including 4.0.4_7 contain a vulnerability in the IndexFile.remove() and Head.checkout() methods. These methods forward arbitrary keyword arguments into underlying git commands without proper validation, allowing an attacker to use the combination of --pathspec-from-file and --pathspec-file-nul flags to cause Git to treat the entire contents of a specified file as a pathspec. When the pathspec does not match any files, Git outputs the entire file content verbatim in the error message, which GitPython surfaces in the GitCommandError.stderr. This results in an arbitrary file read disclosure to the caller. The vulnerability has a CVSS 3.1 score of 6.5 (medium severity) and is fixed in version 4.0.4_7.

legit

GitPython versions >=0.1.0 and <1.2.0.post0_14 contain a vulnerability in the IndexFile.remove() and Head.checkout() methods. These methods forward arbitrary keyword arguments into git rm and git checkout commands without proper validation. When used with the --pathspec-from-file and --pathspec-file-nul options, this can cause Git to treat the entire contents of a specified file as a single pathspec, leading to the file's contents being leaked in error messages returned by GitPython. This allows an attacker with limited privileges to read arbitrary files on the system through error output.

cruft

CVE-2026-76217 is a vulnerability in GitPython where the methods IndexFile.remove() and Head.checkout() forward arbitrary keyword arguments to git rm and git checkout commands without proper validation. When used with the --pathspec-from-file and --pathspec-file-nul options, this can cause Git to treat the entire contents of a specified file as a single pathspec, leading to an error message that includes the entire file content in the command's stderr output. This results in an arbitrary file read disclosure to the caller. The issue affects GitPython versions from 2.9.0 up to but not including 2.16.0_14 and has been fixed in version 2.16.0_14.

cf2tf

gitpython

GitPython versions before 3.1.58 contain a vulnerability where options passed to git rm and git checkout commands in IndexFile.remove() and Head.checkout() are not properly validated. This allows attackers to supply parameters that can read arbitrary files accessible to the process, with file contents exposed in error messages.

Search: CVE-2026-76217