MCPVault: PathFilter restricted-directory deny-list bypass via case and trailing dot/space equivalence
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.
Summary
MCPVault is a lightweight Model Context Protocol server for safe access to files in an Obsidian vault. Prior to 0.11.4, PathFilter in src/pathfilter.ts compiles restricted-directory patterns case-sensitively and compares paths without canonicalizing filesystem-equivalent segment names. On case-insensitive macOS and Windows filesystems, case variants of .git, .obsidian, or node_modules pass both isAllowed() and isAllowedForListing() even though the operating system opens the restricted directory, and Windows trailing dots or spaces provide the same bypass. An attacker who influences a path selected by an AI agent can use the bypass in read, write, move, search, or listing operations to expose or modify sensitive repository and Obsidian metadata. Vault-root .. containment is not affected. This issue is fixed in version 0.11.4.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| bitbonsai | mcpvault | before 0.11.4 | 0.11.4 | Patch available | CNA |
| — | @bitbonsai/mcpvault (npm) | before 0.11.4 | 0.11.4 | Patch available | GHSA-j99q-93c9-h869 |
- mcpvault Vendorbitbonsai Affected before 0.11.4 Fixed in 0.11.4 Patch available CNA
- @bitbonsai/mcpvault (npm) Vendor— Affected before 0.11.4 Fixed in 0.11.4 Patch available GHSA-j99q-93c9-h869
Remediation
- Fix · CNA mcpvault (bitbonsai) Fixed in 0.11.4
- Fix · GHSA-j99q-93c9-h869 @bitbonsai/mcpvault (npm) Fixed in 0.11.4 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-57441
- 2026-10-03 Alias added: GHSA-j99q-93c9-h869
References
More bitbonsai vulnerabilities
- TI-2026-41379 MCPVault: PathFilter restricted directories (.git/.obsidian/node_modules) only denied at vault root, not nested CVSS 4.0MEDIUM 6.9
Sources
- CVE-2026-57441 · CVE Program
- CVE-2026-57441 · NVD
- FIRST EPSS
- GHSA-j99q-93c9-h869 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences