Find notable cyber news and cases, enriched with sources, timelines, and signals.
Home Watchlists Beta Browse News Feed Stats About Contact

Official MCP Python SDK credential-theft fix release (1.30.0, 2.2.0)

Security Patch Release
First reported
Last updated
Happening score
H score 29
1 unique sources, 1 articles

Summary

Hide ▲

The official MCP Python SDK shipped fixed releases that close an OAuth credential-stealing flaw affecting 1.x and 2.x clients. The patch is available in 1.30.0 and 2.2.0, which add issuer-check behavior before login details are fetched. The release matters because affected clients could send the client secret, authorization code, and PKCE proof key to an attacker-controlled endpoint.

Timeline

  1. 29.09.2026 09:08 2 articles · 1h ago

    MCP Python SDK adds issuer checks in 1.30.0 and 2.2.0

    Mitigation Patch Update

    The official MCP Python SDK shipped issuer-check behavior in the 1.30.0 and 2.2.0 release notes on September 7, requiring the client to confirm the expected login service before it fetches authorization details and refusing mismatched issuers.

    Show sources
    Open in new tab
  2. 29.09.2026 09:08 1 articles · 1h ago

    Security advisory warns of OAuth credential theft via malicious MCP server

    Initial Disclosure

    A security advisory warned that a malicious MCP server could trick applications built on the official MCP Python SDK into sending the client secret, authorization code, and PKCE proof key to an attacker-controlled token endpoint, affecting 1.9.1 through 1.29.1 on the 1.x line and 2.0.0 through 2.1.1 on the 2.x line.

    Show sources
    Open in new tab