Next cycleWhy this label: EPSS 2.8%, added 35 days ago

CVE-2026-7273Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability

Product: Zyxel GS1900 Series Switches
Added to CISA KEV: September 21, 2026
Deadline for US federal agencies: September 24, 2026
Known ransomware use: Not known
EPSS, next 30 days: 2.8%, higher than 86% of scored CVEs (Oct 25, 2026)
Weakness: CWE-121

What CISA says

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.

What CISA asks you to do

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.

Sources

Also exploited recently

Data from CISA's Known Exploited Vulnerabilities catalog (public domain) and FIRST EPSS, refreshed hourly. Rheono did not find or test this vulnerability; this page summarizes public sources.