No. CVE-2026-7273
Zyxel GS1900 switches can be taken over from the local network
Being used now
Yes. Attackers are using this right now.
Offices and homes with a Zyxel GS1900 series network switch.
What to do
Apply Zyxel's firmware update for your GS1900 switch.
Confirmed in attacksSep 21, 2026
ProductZyxel GS1900 Series Switches
Attack likelihood, next 30 days2.8%
Attack likelihood is EPSS, a daily estimate from FIRST.org of how likely this bug is to be used in attacks in the next 30 days.
The official description
Zyxel GS1900 series switches contain a stack-based buffer overflow vulnerability in the CGI program which could allow a LAN-based, unauthenticated attacker to exploit the flaw and potentially execute OS commands via a crafted HTTP request.
For your tech helper or AI assistant
A read-only checklist. Paste it into Claude, ChatGPT or a coding agent; it only looks and changes nothing.
Read-only check, change nothing, send nothing anywhere.
Is Zyxel GS1900 Series Switches (CVE-2026-7273) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2026-7273. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.