CVE-2026-86439High· 8.8▾ Twilightknowns versions before 0.30.0 fail to validate filesystem paths in MCP tool arguments, allowing attackers to read, create, overwrite and delete files outside the project directory. Attackers can supply path arguments containing directory…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 48.4 · likelihood 0.2 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Sep 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.8%
0.8% → 1.1%
knowns versions before 0.30.0 fail to validate filesystem paths in MCP tool arguments, allowing attackers to read, create, overwrite and delete files outside the project directory. Attackers can supply path arguments containing directory traversal sequences to access arbitrary Markdown files accessible to the server process.
Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Affected packages:
knowns <= 0.29.1Patched in:
knowns 0.30.0Connected by shared product, vendor, weakness, or advisory.
GHSA-qjrq-cvv4-3g9wHigh· 8.8Duplicate Advisory: Knowns Unrestricted Path Traversal leading to out-of-bounds arbitrary .md file read, write, and deletion in MCP Docs + Memory Tools
CVE-2026-86538High· 7.5knowns versions before 0.30.0 contain a path traversal vulnerability in the POST /api/templates/preview endpoint that allows unauthenticated attackers to read arbitrary files
CVE-2026-86544High· 8.1knowns versions before 0.30.0 contain an authorization bypass vulnerability where mutating code actions are incorrectly classified as read-only operations
CVE-2026-86541High· 8.3knowns versions before 0.30.0 contain a path traversal vulnerability in the handleCodeReplace() function that allows attackers to overwrite arbitrary files outside the project root
CVE-2026-86542Critical· 9.1knowns before 0.30.0 fails to validate import names in the import routes, allowing unauthenticated attackers to write files outside the imports directory
CVE-2026-86543Critical· 9.8knowns versions before 0.30.0 serve the management API without authentication on all network interfaces by default, with no password required on fresh installations