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.
CISA name: Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
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.
Federal remediation due: 2026-09-24
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HDerived from NVD CPE configurations
Schedule remediation and monitor for exploitation.
Recommendation, not a confirmed directive · score is composed only of the factors shown above