CVE-2026-65056: Server-Side Request Forgery (SSRF) in mzxrai mcp-webresearch

CVE-2026-65056 is a server-side request forgery vulnerability in mzxrai's mcp-webresearch 0.1.7. The visit_page tool accepts a URL argument controlled by an attacker, which is only checked for protocol validity but not for private or reserved IP ranges. This allows attackers to direct the server's Playwright browser to internal network endpoints such as cloud instance metadata services. As a result, sensitive internal content, including credentials, may be exposed to the attacker via the model context. The vulnerability has a CVSS 4.0 base score of 8.3, indicating high severity. No official patch or remediation guidance is currently available, and no known exploits in the wild have been reported.

An attacker can leverage this SSRF vulnerability to access internal network services that are normally inaccessible externally. This includes cloud instance metadata endpoints that may contain sensitive credentials or configuration data. The exposure of such internal information can lead to further compromise of the server or cloud environment. The vulnerability requires no privileges and no user interaction other than supplying a crafted URL, increasing its risk.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the visit_page tool or implement network-level controls to prevent the server from making requests to internal or reserved IP ranges. Validate and sanitize URL inputs to block private, loopback, link-local, and cloud metadata IP addresses. Monitor for unusual internal requests originating from the application.