OpenHands is Vulnerable to Command Injection through its Git Diff Handler

## Summary A Command Injection vulnerability exists in the `get_git_diff()` method at `openhands/runtime/utils/git_handler.py:134`. The `path` parameter from the `/api/conversations/{conversation_id}/git/diff` API endpoint is passed unsanitized to a shell command, allowing authenticated attackers to execute arbitrary commands in the agent sandbox. The user is already allowed to instruct the agent to execute commands, but this bypasses the normal channels. --- ## Details ### Vulnerable Code Path The vulnerability flows through these files: 1. **API Endpoint** (`openhands/server/routes/files.py:267-277`) ```python @app.get('/git/diff') async def git_diff( path: str, # <-- User input from HTTP request ... ): ... diff = await call_sync_from_async(runtime.get_git_diff, path, cwd) # No sanitization ``` 2. **Runtime** (`openhands/runtime/base.py:1231-1233`) ```python def get_git_diff(self, file_path: str, cwd: str) -> dict[str, str]: self.git_handler.set_cwd(cwd) return self.git_handler.get_git_diff(file_path) # Passed directly ``` 3. **Vulnerable Method** (`openhands/runtime/utils/git_handler.py:10-12, 134`) ```python # Command template with placeholder GIT_DIFF_CMD = 'python3 /openhands/code/openhands/runtime/utils/git_diff.py "{file_path}"' # Line 134 - VULNERABLE: User input directly interpolated result = self.execute(self.git_diff_cmd.format(file_path=file_path), self.cwd) ``` 4. **Shell Execution** (`openhands/runtime/utils/git_diff.py:25-27`) ```python def run(cmd: str, cwd: str) -> str: result = subprocess.run( args=cmd, shell=True, # <-- Enables shell metacharacter interpretation stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=cwd ) ``` ### Root Cause The `file_path` parameter is directly interpolated into a shell command string using Python's `.format()` method without any sanitization. When this command is executed with `shell=True`, shell metacharacters like `"`, `;`, and `#` are interpreted, allowing command injection. **Example:** - Input: `test"; id #` - Constructed command: `python3 /script.py "test"; id #"` - Shell interprets as two commands: `python3 /script.py "test"` AND `id` --- ## Impact ### Who is Affected - All OpenHands deployments exposing the `/api/conversations/{id}/git/diff` endpoint - Any authenticated user can exploit this vulnerability, ### Attack Capabilities An attacker can: 1. **Execute arbitrary commands** on the runtime container as root 2. **Read sensitive files** including `.env`, API keys, source code 3. **Write arbitrary files** to inject malicious code 4. **Establish reverse shells** for persistent access 5. **Potentially escape the container** if Docker is misconfigured ## Mitigation Users should update to the latest version of OpenHands that includes the changes from PR #13051. The fix replaces direct shell string formatting with proper argument array handling or rigorous path sanitization to prevent command chaining.