MCP Filesystem parent-directory TOCTOU write bypass

Evidence record

Read the original source ↗

Claim-level citations (2)

• supportsMCP Filesystem directory-race fix remained incomplete on Windows: The official filesystem advisory distinguishes a pinned Unix write from a residual Windows path-string write vulnerable to junction replacement between checking a parent and acting on a child.

  Parent-directory fallback TOCTOU; Windows partly fixed; issue 5260

• supportsMCP Filesystem directory-race fix remained incomplete on Windows: GHSA-53mr-w429-c597 documents an ENOENT parent-validation race and distinguishes a handle-based Unix improvement in 2.0.1 from a remaining Windows junction-swap exposure.

  TOCTOU advisory; parent fallback and Windows partly-fixed notes