CVE-2026-55604

Description

DeepSeek MCP Server is an MCP server for DeepSeek V4. Starting in version 1.4.2 and prior to version 1.7.0, the process-global `SessionStore` accepts caller-supplied `session_id` values without binding them to any authenticated principal or transport session. An attacker can enumerate active session IDs via `deepseek_sessions`, then reuse a victim-controlled `session_id` in `deepseek_chat` to retrieve and continue the victim's conversation context. Version 1.7.0 contains a patch.

CVSS Vector

References

• https://github.com/arikusi/deepseek-mcp-server/releases/tag/v1.7.0
• https://github.com/arikusi/deepseek-mcp-server/security/advisories/GHSA-fh3r-g96v-f578
• https://github.com/arikusi/deepseek-mcp-server/security/advisories/GHSA-fh3r-g96v-f578