Vulnerability Intelligence Report
Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
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.
CISA KEV
SSVC: Active Exploitation
CVSS Base Score
8.8
HIGH
Exploitability:2.9
Impact Score:5.9
EPSS Probability:0.32%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-121 ↗CWE-121 Stack-based buffer overflow
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Zyxel | GS1900-48HPv2 firmware | <= 2.90(ABTQ.1)C0 (affected) |
| Zyxel | GS1900-8 firmware | <= 2.90(AAHH.1)C0 (affected) |
| Zyxel | GS1900-8HP firmware | <= 2.90(AAHI.1)C0 (affected) |
| Zyxel | GS1900-10HP firmware | <= 2.90(AAZI.1)C0 (affected) |
| Zyxel | GS1900-16 firmware | <= 2.90(AAHJ.1)C0 (affected) |
| Zyxel | GS1900-24 firmware | <= 2.90(AAHL.1)C0 (affected) |
| Zyxel | GS1900-24E firmware | <= 2.90(AAHK.1)C0 (affected) |
| Zyxel | GS1900-24EP firmware | <= 2.90(ABTO.1)C0 (affected) |
| Zyxel | GS1900-24HPv2 firmware | <= 2.90(ABTP.1)C0 (affected) |
| Zyxel | GS1900-48 firmware | <= 2.90(AAHN.1)C0 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Zyxel Corporation · Vendor · Taiwan |
| Reserved | 2026-04-28T06:21:36 |
| Published | 2026-06-16T02:20:29 |
| Last Updated | 2026-09-21T19:58:23 |
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