CVE-2026-89040NVD

Vulnerability Summary

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.

Severity Level

CRITICAL(9.8)

Published Date

Sep 15, 2026

Last Modified

Sep 22, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.93%Probability

Root Weakness (CWE)

CWE-22: Path Traversal ↗

The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory.

CVSS v4.0 Base Metrics — Score 9.3 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Attack RequirementsNone

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)High

Integrity (Vulnerable System)High

Availability (Vulnerable System)High

Confidentiality (Subsequent System)None

Integrity (Subsequent System)None

Availability (Subsequent System)None

CVSS v3.1 Base Metrics — Score 9.8 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Tencent Mass Service Engine in Cluster (MSEC) < *

Patched Versions

Tencent Mass Service Engine in Cluster (MSEC) *

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