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 via prompt injection. The tool validates only the URL protocol but fails to restrict access to private or reserved IP ranges, enabling attackers to direct the server's Playwright browser to internal network services, including cloud instance metadata endpoints. This can cause sensitive internal page content, including credentials, to be exposed within the model context. The vulnerability has a CVSS 4.0 base score of 8.3, indicating high severity. No patch or official remediation is currently documented, and no known exploits in the wild have been reported.

Successful exploitation allows an unauthenticated attacker to perform SSRF attacks that access internal network services and cloud metadata endpoints. This can lead to disclosure of sensitive internal information, including credentials, which may compromise the confidentiality of internal systems. The vulnerability affects the confidentiality and partially the integrity of the affected system by exposing internal data to the attacker.

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 to trusted users only and consider implementing network-level protections to block unauthorized internal requests. Validate and filter URL inputs to exclude private, loopback, and cloud metadata IP ranges to prevent SSRF exploitation.