CVE-2026-89040

Tencent Mass Service Engine in Cluster (MSEC) allows a remote, unauthenticated attacker to send a crafted POST request including ../ and gain root access on the target device. An attacker who uploads a webshell can execute arbitrary code as root.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/Tencent/MSEC
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-258-02.json
https://www.cve.org/CVERecord?id=CVE-2026-89040

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 20:19

Updated : 2026-09-15 20:19

NVD link : CVE-2026-89040

Mitre link : CVE-2026-89040

CVE.ORG link : CVE-2026-89040

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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