Organizations should check Zyxel security advisories for firmware updates addressing CVE-2026-7273. Prioritize rapid remediation of KEV Catalog vulnerabilities on publicly exposed assets. Apply defense-in-depth measures such as network segmentation and monitoring for anomalous switch behavior.
Quick answers
What is CVE-2026-7273?
Organizations should check Zyxel security advisories for firmware updates addressing CVE-2026-7273. Prioritize rapid remediation of KEV Catalog vulnerabilities on publicly exposed assets. Apply defense-in-depth measures such as network segmentation and monitoring for anomalous switch behavior.
How severe is CVE-2026-7273?
high
Is CVE-2026-7273 known to be exploited?
It is not marked known-exploited in this record.
How should CVE-2026-7273 be mitigated?
Organizations should check Zyxel security advisories for firmware updates addressing CVE-2026-7273. Prioritize rapid remediation of KEV Catalog vulnerabilities on publicly exposed assets. Apply defense-in-depth measures such as network segmentation and monitoring for anomalous switch behavior.
CVSS
—
Vendor
Zyxel
Published
Sep 30, 2026 · 08:05
Patch
Unknown / not confirmed
Affected products
GS1900 Series Switches
Mitigation
Organizations should check Zyxel security advisories for firmware updates addressing CVE-2026-7273. Prioritize rapid remediation of KEV Catalog vulnerabilities on publicly exposed assets. Apply defense-in-depth measures such as network segmentation and monitoring for anomalous switch behavior.
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added CVE-2026-7273, a stack-based buffer overflow in Zyxel GS1900 series switches, to its Known Exploited Vulnerabilities (KEV) catalog. The flaw, with a CVSS score of 8.8, could allow attackers to execute arbitrary code and gain SYSTEM-level access. Patches have been released by Zyxel, and CISA urges immediate remediation.
On September 21, 2026, the Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026-7273 to its Known Exploited Vulnerabilities (KEV) Catalog. The vulnerability is a stack-based buffer overflow in Zyxel GS1900 Series Switches. CISA's action is based on evidence of active exploitation in the wild. Binding Operational Directive 26-04 requires Federal Civilian Executive Branch agencies to prioritize rapid remediation of KEV Catalog vulnerabilities on publicly exposed assets that grant total control post-exploitation.
