CVE-2026-7273
Zyxel · published 2026-06-16
Source record Collected from the National Vulnerability Database (NVD)
CISA Known Exploited Vulnerabilities
CISA lists this CVE as known exploited (added 2026-09-21).
- CISA's name for it: Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
- CISA's description: 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.
- Known ransomware campaign use, per CISA: Unknown
Source: CISA KEV catalog (CC0 1.0).
Description
Description by Zyxel Corporation via the CVE Program.
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.
Status at the source
- NVD status: Analyzed
Affected products, as the source lists them
| Vendor | Product | 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 |
Products named in NVD's CPE match criteria (10)
cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-24ep_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-24hpv2_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:gs1900-48hpv2_firmware:*:*:*:*:*:*:*:*
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 3.1: 8.8 HIGH — as published by Zyxel Corporation (Secondary)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - SSVC — CISA's assessment (SSVC 2.0.3, CISA Coordinator): Exploitation: active · Automatable: no · Technical impact: total
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- 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
Source dates: published 2026-06-16, last changed 2026-09-22. DeSpy's copy of this version is dated 2026-09-28.
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