CVE-2026-61647
NotebookLM MCP is an MCP server and HTTP service for interacting with Google NotebookLM and exporting generated content to local vault directories. Versions 1.6.0 through 2.0.2 contain a path traversal vulnerability in the `POST /batch-to-vault` endpoint, also exposed through the `batch_to_vault` MCP tool beginning in version 1.7.0, because attacker-controlled `vault_dir` and `slug_prefix` values can cause Markdown and JSON files to be written outside the intended vault directory to any location writable by the server process. Version 2.0.3 sanitizes `slug_prefix` and supports vault containment when `NOTEBOOKLM_VAULT_ROOT` is configured; containment is not enabled if that variable is unset. Users unable to upgrade should run the server as a dedicated unprivileged account restricted to the intended vault, keep the HTTP endpoint limited to localhost, and validate `vault_dir` values supplied by LLMs processing untrusted content.
What this means for your business
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 25% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 7.1
- Weakness
- CWE-22
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-21
- Last modified
- 2026-09-24
- Sources
- NVD