CVE-2026-49987

### Vulnerability Metadata | Field | Detail | | --- | --- | | **Affected Component** | `src/core/git/gitCommand.ts` (`execGitShallowClone`) | | **Impact** | Arbitrary Command Execution / Security Control Bypass | ### Summary The `--remote-branch` CLI option in `repomix` is vulnerable to argument injection. User-supplied input is passed directly to `git fetch` and `git checkout` subprocesses via `child_process.execFileAsync` without sanitization, `--` delimiters, or validation. An attacker can inject arbitrary git command-line options. By injecting the `--upload-pack` option and specifying an SSH (`git@...`) or local (`file://`) remote URL, an attacker achieves arbitrary command execution with the privileges of the user running `repomix`. This bypasses the existing `dangerousParams` blocklist implemented in `validateGitUrl()`. ### Vulnerable Code Analysis **File:** `src/core/git/gitCommand.ts` The `remoteBranch` parameter is appended directly to the arguments array for git subprocesses without the `--` positional delimiter. **Sink 1 (Lines 118-127):** ```typescript await deps.execFileAsync( 'git', ['-C', directory, 'fetch', '--depth', '1', 'origin', remoteBranch], // Vulnerable gitRemoteOpts, ); ``` **Sink 2 (Lines 148-151):** ```typescript await deps.execFileAsync('git', ['-C', directory, 'checkout', remoteBranch]); // Vulnerable ``` **Bypassed Security Control (Lines 192-197):** The application attempts to prevent this exact vulnerability class by blocking dangerous parameters (`--upload-pack`, `--receive-pack`, `--config`, `--exec`) within the `validateGitUrl` function. However, this validation is exclusively applied to the `url` variable and omitted for `remoteBranch`, creating a direct bypass. ### Attack Flow ```text [Source] repomix --remote-branch <injected_option> ↓ src/cli/actions/remoteAction.ts:226 (cloneRepository) ↓ src/core/git/gitCommand.ts:118 (execGitShallowClone) ↓ [Sink] execFileAsync('git', ['...', 'origin', '--uploa