9.3
CRITICAL CVSS 4.0
CVE-2026-11720
Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder
Description

A path traversal vulnerability exists in the HTTP tool URL builder of googleapis/mcp-toolbox. When constructing downstream API requests, the URL builder substitutes user-controlled pathParams into the configured tool path and parses the resulting string as a relative URL. While it checks that the input does not alter the scheme, host, or user info, it relies on ResolveReference for the final URL resolution. Because dot segments (../) are normalized during this resolution step, an attacker can supply path parameters containing directory traversal sequences to escape the operator-configured path scope. This allows the client to coerce the toolbox into making requests to unintended endpoints on the same target host while forwarding the toolbox's configured credentials (e.g., bypassing a restricted path like /api/v1/users/{{.id}} to reach /admin/secrets).

INFO

Published Date :

June 29, 2026, 5:51 p.m.

Last Modified :

June 29, 2026, 5:51 p.m.

Remotely Exploit :

Yes !

Source :

Google
Affected Products

The following products are affected by CVE-2026-11720 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 CRITICAL 14ed7db2-1595-443d-9d34-6215bf890778
Solution
Sanitize user-controlled path parameters to prevent directory traversal in URL resolution.
  • Validate and sanitize all user-supplied path parameters.
  • Avoid direct substitution of user input into URL paths.
  • Implement stricter URL parsing and validation logic.
  • Update the mcp-toolbox library to a secure version.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-11720 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.