CVE-2026-7273

Deferred
Published: 16 Jun 2026, 02:20
Last modified:21 Sept 2026, 19:58

Vulnerability Summary

Overall Risk (default)
medium
35/100
CVSS Score
8.8 HIGH
v3.1 (cve.org)
EPSS Score
0.32% LOW
0% probability 0.00%
KEV
Listed
CISA
1 listing
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

16 Jun 2026, 02:20
Published
Vulnerability first disclosed
21 Sept 2026, 00:00
Added to CISA KEV
Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
21 Sept 2026, 19:58
Last Modified
Vulnerability information updated
24 Sept 2026, 00:00
CISA Remediation Due
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.

Description

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.

CVSS Metrics

  • v3.1•HIGH•Score: 8.8CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.32%• Percentile: 25%

Techniques & Countermeasures

  • CWE-121•Stack-based Buffer Overflow

    A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

Affected Systems

  • zyxel•gs1900-10hp firmware

    ≤ 2.90(AAZI.1)C0

  • zyxel•gs1900-16 firmware

    ≤ 2.90(AAHJ.1)C0

  • zyxel•gs1900-24 firmware

    ≤ 2.90(AAHL.1)C0

  • zyxel•gs1900-24e firmware

    ≤ 2.90(AAHK.1)C0

  • zyxel•gs1900-24ep firmware

    ≤ 2.90(ABTO.1)C0

  • zyxel•gs1900-24hpv2 firmware

    ≤ 2.90(ABTP.1)C0

  • zyxel•gs1900-48 firmware

    ≤ 2.90(AAHN.1)C0

  • zyxel•gs1900-48hpv2 firmware

    ≤ 2.90(ABTQ.1)C0

  • zyxel•gs1900-8 firmware

    ≤ 2.90(AAHH.1)C0

  • zyxel•gs1900-8hp firmware

    ≤ 2.90(AAHI.1)C0

References (3)