According to CoinMeta, as reported by Forkast, there is a credential theft vulnerability in the official MCP Python SDK of Anthropic that allows any malicious server to hijack user logins. This vulnerability was disclosed on September 28th and has been assigned the tracking number GHSA-QX49-FQC8-XW99; its severity score is 7.5 on the vulnerability rating scale. Security company Cycode demonstrated a complete attack chain, showing that the stolen credentials are sufficient to obtain valid access tokens from legitimate identity providers. Affected versions of SDK fail to verify the address of the authorized server during authentication, allowing attackers to exploit this weakness. Fixes for this issue are available in versions 1.30.0 and 2.2.0; after upgrading, organizations should clear any stored OAuth client credentials and rotate the client keys.