9.8

CVE-2026-89040: Tencent Mass Service Engine in Cluster (MSEC) path traversal

Awaiting analysis
Published 15-09-2026Last modified 22-09-2026

Vulnerability summary

CVE-2026-89040 is a critical (CVSS 9.8) vulnerability in tencent mass service engine in cluster (msec). EPSS estimates a 1.14% chance of exploitation in the next 30 days, higher than 66.7% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 9.3 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
1.14%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 15-09-2026
    PublishedVulnerability first disclosed.
  2. 22-09-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

1.14%

Chance of exploitation in the next 30 days

Percentile

67%

Versus all other CVEs

30-day change

No change 0.00 pp

From 1.14% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Tencent1 product

1 vendor · 1 product

References

3 links