MCP Python SDK: Experimental task handlers allow any client to access and cancel other clients' tasks
High-risk advisory
CVE-2026-52870
Summary
MCP Python SDK: Experimental task handlers allow any client to access and cancel other clients' tasks
Why it matters
GitHub has published a reviewed security advisory for mcp. Prioritize it with other application dependency updates, especially because EPSS places it in the 13% percentile.
Operator check
Check whether mcp is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. EPSS probability: 0.2%; percentile: 13%.
Sources
PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.