A AegiFlow
MEDIUMCVSS 5.9EPSS 0.4%

CVE-2026-116685

CVE-2026-116685 updated by NVD

Published
2026-10-27
Modified
2026-11-01
EPSS percentile
34%
Sources
github-advisory, nvd

Summary

The Model Context Protocol Python SDK is the official Python SDK for Model Context Protocol servers and clients. From 1.8.0 until 1.30.0 and 2.2.0, streamable_http_client, streamablehttp_client, sse_client, ClientSessionGroup, OAuth, and create_mcp_http_client client paths enable follow_redirects and follow redirects to a different origin, forwarding caller-supplied custom credential headers and, for 307 or 308 responses, the request body. An attacker who can influence a trusted endpoint's redirect destination can receive that material. This issue is fixed in versions 1.30.0 and 2.2.0.

Affected packages

EcosystemPackageAffected versionsFixed versions
PyPImcp—2.2.0, 1.30.0

Remediation: Upgrade to 2.2.0 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.