CVE-2026-59951Published
MCP Python SDK: Unbounded Session Accumulation in StreamableHTTP Transport Enables Resource Exhaustion
Explicit identifiers and source references
These records connect through source-stated identifiers. Shared identifiers or dates alone do not establish shared exposure, root cause or applicability.
CVE-2026-59951 · Microsoft / collected KEV context
cve-program · CVE-2026-59951
- https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-84m7-p3x7-pcfv
- https://github.com/modelcontextprotocol/python-sdk/pull/3395
- https://github.com/modelcontextprotocol/python-sdk/pull/3426
- https://github.com/modelcontextprotocol/python-sdk/commit/92120b4b0f50385af096592d7cee932fc1d994e7
- https://github.com/modelcontextprotocol/python-sdk/commit/d2290ca3434731b68ea3e2270bc06a6e6575931b
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0
Related operational evidence
Explicit CVE identifiersNo related operational record is retained in the current change model.