CVE-2026-39454
Improper File Permissions in SKYSEA Client View Allow Privilege Escalation
Publication date: 2026-04-20
Last updated on: 2026-04-20
Assigner: JPCERT/CC
Description
Description
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| sky_co.ltd | skysea_client_view | * |
| sky_co.ltd | skymec_it_manager | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-276 | During installation, installed file permissions are set to allow anyone to modify those files. |
Attack-Flow Graph
AI Powered Q&A
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify how CVE-2026-39454 affects compliance with common standards and regulations such as GDPR or HIPAA.
Can you explain this vulnerability to me?
This vulnerability exists in SKYSEA Client View and SKYMEC IT Manager by Sky Co., LTD. The issue is due to improper file access permission settings on the installation folder of these products.
Because of these weak permissions, a non-administrative user can manipulate or place arbitrary files within the installation folder.
This can lead to arbitrary code execution with administrative privileges, meaning an attacker could run malicious code with high-level access.
How can this vulnerability impact me? :
The vulnerability can have serious impacts because it allows a non-administrative user to execute arbitrary code with administrative privileges.
This means an attacker could potentially take full control of the affected system, leading to data theft, system compromise, or disruption of services.
The CVSS scores indicate a high severity, with impacts on confidentiality, integrity, and availability.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability is local in nature and involves improper file access permission settings on the installation folders of SKYSEA Client View and SKYMEC IT Manager products. Detection involves checking the file permissions of the installation directories to identify if non-administrative users have write or modify access.
Since the vulnerability allows non-administrative users to place or manipulate arbitrary files in the installation folder, you can detect it by verifying the permissions on these folders on Windows OS systems.
- Use Windows command line to check folder permissions, for example: icacls "C:\Path\To\InstallationFolder"
- Look for permissions that allow non-administrative users (such as Users group) to write or modify files.
- If such permissions are found, the system is vulnerable.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include applying the patches or updates provided by Sky Corporation for the affected products.
- For SKYSEA Client View users with maintenance contracts, download and apply the update to version 21.210.01f or later, or apply the provided patch to the master server.
- Recreate any installers with department information that were created before applying the fix.
- For SKYSEA Client View M1 Cloud Edition users, ensure new terminal installers are downloaded from the management console as the fix was applied by Sky Corporation.
- For SKYMEC IT Manager users, apply the provided patch module to the master server and await the full update module release.
Additionally, review and correct the file access permissions on the installation folders to prevent non-administrative users from modifying or placing files.