CVE-2026-14540
Server-Side Request Forgery via Unrestricted HTTP Redirection in MCP Toolbox
Description
A Server-Side Request Forgery (SSRF) vulnerability exists in the generic HTTP source and tool components of Google mcp-toolbox versions 0.3.0 through 1.4.0. While the toolbox implements baseline input sanitization for user-controlled parameters, the underlying HTTP client (internal/sources/http/http.go) fails to safely regulate request redirection boundaries. Specifically, the client is initialized without a restrictive CheckRedirect policy hook and lacks target IP validation. An attacker or a malicious data-driven prompt can supply a crafted path parameter that triggers an open redirect or a direct destination swap on the target backend, coercing the mcp-toolbox into blindly following the redirection and making unauthorized requests to internal or arbitrary external endpoints.
INFO
Published Date :
July 31, 2026, 2:16 a.m.
Last Modified :
July 31, 2026, 2:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-14540
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
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | 14ed7db2-1595-443d-9d34-6215bf890778 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update mcp-toolbox to version 1.5.0 or later.
- Configure HTTP client with a restrictive CheckRedirect policy.
- Implement target IP validation for all HTTP requests.
- Sanitize user-supplied URL parameters rigorously.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-14540.
| URL | Resource |
|---|---|
| https://github.com/googleapis/mcp-toolbox/pull/3448 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-14540 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-14540
weaknesses.
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-2026-14540 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-14540 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 31, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Google', 'product': 'mcp-toolbox', 'versions': [{'status': 'affected', 'version': '0.3.0', 'versionType': 'semver', 'lessThanOrEqual': '1.4.0'}], 'defaultStatus': 'unaffected'}] Added Description A Server-Side Request Forgery (SSRF) vulnerability exists in the generic HTTP source and tool components of Google mcp-toolbox versions 0.3.0 through 1.4.0. While the toolbox implements baseline input sanitization for user-controlled parameters, the underlying HTTP client (internal/sources/http/http.go) fails to safely regulate request redirection boundaries. Specifically, the client is initialized without a restrictive CheckRedirect policy hook and lacks target IP validation. An attacker or a malicious data-driven prompt can supply a crafted path parameter that triggers an open redirect or a direct destination swap on the target backend, coercing the mcp-toolbox into blindly following the redirection and making unauthorized requests to internal or arbitrary external endpoints. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-918 Added Reference https://github.com/googleapis/mcp-toolbox/pull/3448