What is CVE-2026-7273?
A stack-based buffer overflow vulnerability in the CGI program of Zyxel GS1900-48HPv2 firmware versions through 2.90(ABTQ.1)C0 could allow a LAN-based, unauthenticated attacker to exploit the flaw and potentially execute OS commands via a crafted HTTP request.
Timeline
- 2026-06-16Published to the U.S. National Vulnerability Database (NVD)
- 2026-09-21Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
- 2026-09-22NVD record last updated
- 2026-09-24CISA federal remediation deadline (BOD 22-01)
CISA Known Exploited Vulnerability
Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
Affected product
Zyxel GS1900 Series Switches
Remediation Steps
- Apply the vendor security patch for Zyxel products
- Identify all affected Zyxel devices in your network inventory
- Restrict network access to affected devices while patches are deployed
- Verify patch installation across all affected systems
References
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-stack-based-buffer-overflow-vulnerability-in-gs1900-series-switches-06-16-2026
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-7273
- https://www.greynoise.io/blog/open-season-on-kapibala-attacker-steals-government-records-wordpress-exploitation
- https://nvd.nist.gov/vuln/detail/CVE-2026-7273
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Referenced in our briefings & reports
- Vulnerability Priority Report – Week 3 of September 2026 (September 21 – 27)
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🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.