CVE-2026-89040CWE-22path-traversal

CVE-2026-89040

Critical · published September 16, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
66.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
9.3 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.01144 · 66.4th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-09-16T00:19Z
References (3)
https://github.com/Tencent/MSEC · 9119a7d8-5eab-497f-8521-727c672e3725https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-258-02.json · 9119a7d8-5eab-497f-8521-727c672e3725https://www.cve.org/CVERecord?id=CVE-2026-89040 · 9119a7d8-5eab-497f-8521-727c672e3725
EPSS history
Timeline
  • 17 SEP 03:33Z
    EPSS moved — → 1%
    epss
  • 15 SEP 20:05Z
    Tencent Mass Service Engine in Cluster (MSEC) path traversal
    cvelistv5