🛡️ CVE-2026-55604

🟠 CVSS 8.6 — High ✅ No Known Exploit CWE-639 NVD
8.6
CVSS Score
0 Low4 Medium7 High9 Critical10

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity low, availability low.

Weakness class

CVE-2026-55604 is classified as CWE-639: Authorization Bypass Through User-Controlled Key. An object is selected by an identifier from the request without checking the caller owns it.

Affected software

CVE-2026-55604 is recorded against 1 package.

  • unknown

Timeline and source

Published on 9 July 2026 and last revised on 10 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

github.com
github.com
github.com

Details

Severity HIGH
CVSS Score 8.6
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
CWE CWE-639
Public Exploit ✅ No
Source NVD
Published 2026-07-09
Updated 2026-08-11
Modified 2026-07-10
Fix URL N/A

Affected Packages

Software From version Fixed in
unknown — —

Similar Threats

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