22 September 2026
Reference: CVE-2026-7273
1. What is being reported?
The Zyxel GS1900-48HPv2 network switches have a software flaw that can be triggered by a specially crafted web request. This flaw could let someone on the same local network run commands on the switch without needing to log in, potentially taking control of it.
2. What this means in plain English
If an attacker gains control of your network switch, they could disrupt your internet connection, spy on your network traffic, or use your network to attack others. This risk is higher if the switch is accessible to many users or poorly secured.
3. Could this affect a small business?
Small businesses or organisations using Zyxel GS1900 Series switches, especially the GS1900-48HPv2 model with certain firmware versions, could be affected. If you do not use this equipment, you are not at risk from this specific issue.
4. What to do now
- Check if you have Zyxel GS1900 Series switches, particularly the GS1900-48HPv2 model.
- Contact your IT provider or Zyxel support to confirm if your switch firmware is vulnerable and to get instructions for applying any available updates or mitigations.
- If no update is available, follow vendor guidance on mitigating the risk or consider replacing the device.
- Ensure your network is segmented and restrict access to network switches to trusted users only.
5. Ask your IT provider
Can you confirm if our Zyxel GS1900 Series switches are affected by the CVE-2026-7273 vulnerability, and have we applied all recommended security updates or mitigations?
6. Bottom line
If you use Zyxel GS1900 switches, act now to secure them against an actively exploited vulnerability that could let attackers take control of your network.
Information based on CISA KEV, NVD and reputable security news reports.