Vulnerability in Model Context Protocol Python SDK Allows Credential Exposure
CVE-2026-116685
5.9MEDIUM
What is CVE-2026-116685?
The Model Context Protocol Python SDK has a vulnerability that affects various client paths, allowing malicious actors to exploit follow_redirects settings. When certain versions of the SDK handle HTTP responses with status codes 307 or 308, they can inadvertently forward custom credential headers and the request body to an untrusted origin if an attacker can manipulate the redirect destination. This poses a risk of credential exposure, making it crucial for users to update to versions 1.30.0 or 2.2.0, where the issue has been addressed.
Affected Version(s)
python-sdk >= 1.8.0, < 1.30.0 < 1.8.0, 1.30.0
python-sdk >= 2.0.0, < 2.2.0 < 2.0.0, 2.2.0