Summary
| Parameter | Value |
|---|---|
| CVE ID | CVE-2026-7273 |
| Alert Source | CISA KEV - Active Exploitation |
| CVE Publication Year | 2026 |
| Date Published | 2026-09-21 |
| Vendor | Zyxel |
| Product | GS1900 Series Switches |
| CVSS Score | 8.8 (high) |
| EPSS Score | 2.4% (percentile: 83%) |
| CISA KEV | Yes - confirmed active exploitation |
| Ransomware | Not confirmed |
| Remediation Deadline | 2026-09-24 |
Vulnerability 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.
Required Actions
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset’s internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Who Is Affected?
This vulnerability affects GS1900 Series Switches by Zyxel. Check if your organization uses this software and requires updates.
Sources
Need help securing your systems? nFlo team offers vulnerability management and 24/7 SOC services. Contact us.
