CVE-2026-57441: Bitbonsai Mcpvault

High severity, CVSS 8.4. EPSS: 0.2% chance of exploitation in the next 30 days.

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.

Affected products

• Bitbonsai Mcpvault: before 0.11.4 (fixed in 0.11.4)

Published 2026-09-15. Last modified 2026-09-30.