Risk Letters

Exploited vulnerability

CVE-2026-7273

TLP:CLEAR

Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability

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.

Facts

  • Vendor: Zyxel
  • Product: GS1900 Series Switches
  • CVSS: 8.8
  • EPSS (probability of exploitation within 30 days): 2.8 %
  • On CISA's Known Exploited Vulnerabilities list since: 21 September 2026
  • First known exploitation: 21 September 2026
  • CISA's deadline for US federal agencies: 24 September 2026
  • Weakness: CWE-121
  • First seen by Risk Letters: 16 June 2026

Members see which Nordic sectors the flaw hits, and what to do about it.

Get the full brief

Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD