CVE-2026-39454

Administrative code execution via writable installation folder

Published Apr 20, 2026 · Updated Apr 20, 2026

Incorrect default permissions in affected SKYSEA Client View and SKYMEC IT Manager releases allow local users to gain administrative code execution. Affected Windows installers create the product installation folder with access controls that let non-administrative users alter existing files or place arbitrary files there. The issue affects SKYSEA Client View 21.200.07j and earlier and SKYMEC IT Manager 2024.005.10a and earlier; exploitation requires local low-privilege access during installation.

CVSS severity8.5
High
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect default permissions in affected SKYSEA Client View and SKYMEC IT Manager releases allow local users to gain administrative code execution. Affected Windows installers create the product installation folder with access controls that let non-administrative users alter existing files or place arbitrary files there. The issue affects SKYSEA Client View 21.200.07j and earlier and SKYMEC IT Manager 2024.005.10a and earlier; exploitation requires local low-privilege access during installation.

The record

CVE
CVE-2026-39454
Published
Apr 20, 2026
Updated
Apr 20, 2026
Vendor
Sky Co., Ltd.
Product
SKYMEC IT Manager
Classifications
CWE-863, CWE-276, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Ver.2024.005.10a and earlier

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Sky Co., Ltd. · SKYMEC IT Managerversion=Ver.2024.005.10a and earlier
Sky Co., Ltd. · SKYSEA Client Viewversion=Ver.21.200.07j and earlier

Published CVSS scores

7.8JPCERT/CCCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.5JPCERT/CCCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
CWE-276Incorrect Default Permissions
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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