{"items":[{"id":"NVI-00013256","kind":"vulnerability","title":"Dulwich: Arbitrary File Write (RCE) on Windows via Unvalidated Drive Letters in Tree Paths","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-8mcx-5rqc-vhmf"],"plain_summary":"GitHub lists this reviewed advisory for dulwich. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-a84787c97eef0ae80b7f5c3f1b088329"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-02T19:14:22.000Z","value":"8.8 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-a84787c97eef0ae80b7f5c3f1b088329"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-a84787c97eef0ae80b7f5c3f1b088329","url":"https://github.com/advisories/GHSA-8mcx-5rqc-vhmf","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-8mcx-5rqc-vhmf","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T01:40:00.567Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-a84787c97eef0ae80b7f5c3f1b088329"],"technology":"dulwich","known_exclusions":[],"conditions_summary":"### Affected files\n* `dulwich/index.py` (Methods: `validate_path_element_ntfs`, `_tree_to_fs_path`)\n* `dulwich/porcelain/__init__.py` (Method: `_checked_worktree_path`)\n\n### Description / Summary\nA High-severity Path Traversal vulnerability exists in Dulwich's checkout logic when running on Windows. The functions responsible for validating NTFS paths strictly reject `.git` variants, Alternate Data Streams (ADS), `git~1` short names, and reserved device names, but they completely fail to check for **DOS drive letter prefixes**.\n\nA malicious Git tree can contain an entry named `C:`. When Dulwich processes this tree on a Windows client, the string passes the `validate_path_element_ntfs` check. Later, `_tree_to_fs_path` passes this path to `os.path.join(root, b\"C:\\\\\\\\Users\\\\\\\\...\")`. \n\nOn Windows, if the second argument to `os.path.join` contains an absolute drive letter, the `root` path is completely discarded. As a result, Dulwich writes the repository file to the absolute path outside of the intended Git worktree.\n\nWhile the standard C `git` client explicitly blocks this via `has_dos_drive_prefix()` in `path.c`, Dulwich lacks this protection. Because Git trees are cross-platform, an","public_affected_ranges":["< 1.2.9"]}],"null_published_at":"2026-11-01T07:29:12.932Z","source_updated_at":"2026-10-02T19:14:22.000Z","source_disclosed_at":"2026-10-02T19:14:21.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-01T01:40:00.567Z"}],"next_cursor":null,"snapshot_revision":"42594"}