CVE-2026-67431

creationtimestamp| type| source ---|---|--- 2026-07-29 21:21:23+00:00| seen| https://bsky.app/profile/cve.skyfleet.blue/post/3mrsu6t2mfx2q 2026-07-30 16:35:20+00:00| published-proof-of-concept| https://github.com/modelcontextprotocol/ruby-sdk/security/advisories/GHSA-5p9g-j988-pcwv 2026-07-31...

CVE-2026-67431

The CVE affects the MCP Ruby SDK (Model Context Protocol) prior to version 0.23.0. In MCP::Server::Transports::StreamableHTTPTransport, the session ID is not bound to a session owner, allowing a stolen session ID to cause requests (tools/call) to execute in the victim’s session. This is fixed in ...