U.S. CISA adds Zyxel flaw to its Known Exploited Vulnerabilities catalog
CISA added exploited Zyxel GS1900 switch flaw CVE-2026-7273 to the KEV catalog, with a September 24 fix deadline.
CISA added CVE-2026-7273, a stack-based buffer overflow in the CGI program of Zyxel GS1900 series switch firmware, to the Known Exploited Vulnerabilities catalog. The flaw, scored CVSS 8.8, lets an unauthenticated attacker on the local network send a crafted HTTP request and potentially execute operating-system commands. Zyxel patched affected models in 2.90 firmware builds, and federal civilian agencies must remediate by September 24, 2026. CISA did not name attackers; researchers at ISCAS are credited with the report.
- CVE-2026-7273 is a stack-based buffer overflow in Zyxel GS1900 CGI firmware, CVSS 8.8.
- Unauthenticated LAN attackers can run OS commands via a crafted HTTP request.
- Patches are the 2.90 second-release firmware builds for affected GS1900 models.
- Federal agencies must remediate by September 24, 2026, under BOD 22-01.
- CISA named no attackers; ISCAS researchers are credited with the report.
- CVEs
- CVE-2026-7273
- Vendors
- Zyxel
- Products
- GS1900
- Countries
- United States
Vulnerabilities mentioned
All| CVE | Vulnerability | CVSS | EPSS | Signals | Published |
|---|---|---|---|---|---|
| CVE-2026-7273 | Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability | 8.8 | 3% | KEVPoC | KEV |
From the original article
2 min read at securityaffairs.com
U. S. Cybersecurity and Infrastructure Security Agency (CISA) adds Zyxel flaw to its Known Exploited Vulnerabilities catalog.
By Pierluigi Paganini · securityaffairs.com
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