How to Fix CVE-2016-7836: Remote Code Execution in SKYSEA Client View
By Sai Kiran Pandrala
| Severity | CVSS 9.8 - Critical |
|---|---|
| Actively exploited? | Yes, listed in CISA KEV (added 2025-10-14) |
| Affected | SKYSEA Client View Ver.11.221.03 and earlier |
| Fixed in | See vendor advisory |
| Type (CWE) | Not verified - see official advisory |
Patch immediately. CISA added CVE-2016-7836 to the Known Exploited Vulnerabilities catalog on 2025-10-14. Federal civilian agencies must remediate by 2025-11-04. Treat every internet-reachable instance as a priority patch.
What is CVE-2016-7836?
CVE-2016-7836 is a Remote Code Execution flaw in Sky Co., LTD. SKYSEA Client View. It carries a CVSS base score of 9.8 (critical). CISA confirmed real-world exploitation by adding it to the Known Exploited Vulnerabilities catalog on 2025-10-14.
From the source record: SKYSEA Client View Ver.11.221.03 and earlier allows remote code execution via a flaw in processing authentication on the TCP connection with the management console program.
Why it matters in practice: KEV-listed CVEs draw continuous internet-wide scanning. Any unpatched, internet-reachable installation is on borrowed time. The blast radius depends on how the affected service is exposed. An internet-facing instance with no compensating controls is the highest-risk configuration.
Am I affected?
You are affected if your installation of SKYSEA Client View matches a version listed in the Affected row above.
Check the installed version of SKYSEA Client View against the Affected row above. If the version sits at or below the affected range and the vendor patch has not been applied, you are vulnerable.
How to fix CVE-2016-7836
Apply the vendor patch. Target the patched build listed on the vendor advisory. The runnable command set below covers the most common deployment patterns for SKYSEA Client View.
Generic upgrade path
# Debian / Ubuntu
sudo apt-get update && sudo apt-get install --only-upgrade skysea
# RHEL / Rocky / Alma
sudo dnf upgrade --security -y
# Windows
# PowerShell:
# winget upgrade --all --silent --accept-package-agreements --accept-source-agreements
# macOS
sudo softwareupdate -i -a -R
After applying the patch
- Restart the service or device so the patched binary loads.
- Confirm the running version matches the Fixed in row using the verification command below.
- Rotate credentials and API keys that the affected service could access if the asset was exposed during the disclosure window.
If you can't patch immediately
Until the patch lands, narrow the attack surface with these runnable controls.
Reduce the attack surface
Restrict network reach to the affected service to the smallest set of hosts that must access it. On Linux:
# Vendor advisory: https://www.skyseaclientview.net/news/161221/
sudo iptables -A INPUT -p tcp --dport <service-port> -s 10.10.10.0/24 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport <service-port> -j DROP
On Windows:
# Vendor advisory: https://www.skyseaclientview.net/news/161221/
New-NetFirewallRule -DisplayName "Block CVE-2016-7836 inbound" -Direction Inbound -Action Block -Protocol TCP -LocalPort <service-port>
Mitigations are temporary. Apply the vendor patch as soon as a maintenance window opens.
How to verify the fix worked
Confirm the patched build is the one actually running.
Run the product's --version or about command and compare against the Fixed in row (See vendor advisory). Re-run an authenticated vulnerability scan and confirm the scanner no longer flags CVE-2016-7836.
Also worth doing: pull recent log windows for any indicators of compromise listed in the vendor advisory, and re-run an authenticated vulnerability scan with up-to-date signatures.
Frequently asked questions
Related fixes
Other vulnerabilities in the same area that are worth patching alongside this one:
- How to Fix CVE-2016-20017: Improper Neutralization of Special Elements used in a Command ('Command Injectio — Improper Neutralization of Special Elements used in a Command ('Command Injectio
- How to Fix CVE-2016-3976: n/a in n/a — n/a in n/a
- How to Fix CVE-2016-3235: n/a in n/a , n/a in n/a
- How to Fix CVE-2016-2386: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injecti , Improper Neutralization of Special Elements used in an SQL Command ('SQL Injecti
- How to Fix CVE-2016-3715: n/a in n/a , n/a in n/a
Is CVE-2016-7836 being exploited in the wild?
Yes. CISA added CVE-2016-7836 to the Known Exploited Vulnerabilities catalog on 2025-10-14. KEV listing means at least one confirmed real-world exploitation report exists.
Do I have to take downtime to patch?
For most Sky Co., LTD. SKYSEA Client View deployments, the patched build needs a service restart or device reboot. HA pairs and clusters can roll the upgrade by patching the standby first, failing over, then patching the former primary.
Will a WAF or IDS rule alone close CVE-2016-7836?
No. Network filters cut down opportunistic scans but they do not remove the flaw. The vendor patch is the only durable fix.
Why is CVE-2016-7836 rated critical?
The CVSS base score of 9.8 reflects network reach, low attack complexity, and high impact on confidentiality, integrity, and availability. That combination is what the rating model maps to critical.
References
- Official vendor advisory: https://www.skyseaclientview.net/news/161221/
- NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2016-7836
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- CISA KEV entry: "SKYSEA Client View Improper Authentication Vulnerability" - added 2025-10-14, due 2025-11-04
- Additional reference: http://www.securityfocus.com/bid/95062
- Additional reference: http://www.skyseaclientview.net/news/161221/
- Additional reference: https://jvn.jp/en/jp/JVN84995847/index.html
- Additional reference: https://www.skygroup.jp/security-info/170308.html
*Assembled from the official vendor advisory, the NVD record, and the CISA KEV listing on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*