CVE-2026-45609
mcp-security: Unvalidated URL Fetching (SSRF)
Description
mcp-security provides Security and Authorization support for Model Context Protocol in Spring AI. Prior to 0.1.9, the mcp-security framework fails to implement the mandatory SSRF mitigations outlined in the Model Context Protocol (MCP) security specifications. Specifically, it processes untrusted URLs for OAuth-related discovery and metadata without verifying if the targets are malicious or internal to the network. This only affects installations with Dynamic Client Registration (DCR) enabled This vulnerability is fixed in 0.1.9.
INFO
Published Date :
May 29, 2026, 3:16 p.m.
Last Modified :
June 3, 2026, 2:08 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update mcp-security to version 0.1.9 or later.
- Disable Dynamic Client Registration if unable to update.
- Review and validate all external URLs processed by the framework.
Public PoC/Exploit Available at Github
CVE-2026-45609 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2026-45609.
| URL | Resource |
|---|---|
| https://github.com/spring-ai-community/mcp-security/security/advisories/GHSA-qjp4-4jvr-xqg3 | Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45609 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-2026-45609
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).
Cathedral-Grade Security for AI Agents. Attack vectors updated daily. Local-first, zero API cost. MIT licensed.
Python
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-45609 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45609 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.
-
Initial Analysis by [email protected]
Jun. 03, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:springaicommunity:mcp_security:*:*:*:*:*:*:*:* versions from (including) 0.1.0 up to (excluding) 0.1.9 Added Reference Type GitHub, Inc.: https://github.com/spring-ai-community/mcp-security/security/advisories/GHSA-qjp4-4jvr-xqg3 Types: Mitigation, Vendor Advisory -
New CVE Received by [email protected]
May. 29, 2026
Action Type Old Value New Value Added Description mcp-security provides Security and Authorization support for Model Context Protocol in Spring AI. Prior to 0.1.9, the mcp-security framework fails to implement the mandatory SSRF mitigations outlined in the Model Context Protocol (MCP) security specifications. Specifically, it processes untrusted URLs for OAuth-related discovery and metadata without verifying if the targets are malicious or internal to the network. This only affects installations with Dynamic Client Registration (DCR) enabled This vulnerability is fixed in 0.1.9. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N Added CWE CWE-918 Added Reference https://github.com/spring-ai-community/mcp-security/security/advisories/GHSA-qjp4-4jvr-xqg3