Executive brief
MCPVault, a tool used for managing secure file storage, contains a flaw that allows users to bypass folder restrictions on Windows and macOS. By using different capitalization or adding extra dots and spaces to a folder name, an attacker can access restricted directories like configuration or secret folders. This could lead to the exposure of sensitive internal data or unauthorized modification of files.
Technical details
A path equivalence vulnerability exists in MCPVault's PathFilter component when running on case-insensitive filesystems such as macOS and Windows. The PathFilter implemented its deny-list patterns case-sensitively and matched paths verbatim, failing to account for OS-level canonicalization. Attackers can bypass restrictions on directories like .git or .obsidian by using alternative casing (e.g., .Git) or, on Windows, by appending trailing dots or spaces (e.g., .git.). This allows unauthorized read, write, move, and search operations on restricted paths via the isAllowed and isAllowedForListing functions. The issue is resolved in version 0.11.4 by implementing case-insensitive matching and per-segment path canonicalization.
Affected products
- bitbonsai MCPVault (@bitbonsai/mcpvault) < 0.11.4
Timeline
- 2026-06-17: disclosed: Initial publication by bitbonsai
- 2026-06-18: advisory: GitHub Advisory published
- 2026-06-18: patched: Fixed in version 0.11.4