CVE-2026-55604

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 v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

10 Jul 2026, 16:16

Type	Values Removed	Values Added
References	~~() 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 -

09 Jul 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-09 22:17

Updated : 2026-07-10 19:20

NVD link : CVE-2026-55604

Mitre link : CVE-2026-55604

CVE.ORG link : CVE-2026-55604

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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