{
  "id": "cve-2026-7273",
  "cveID": "CVE-2026-7273",
  "vendor": "Zyxel",
  "product": "GS1900 Series Switches",
  "vulnerabilityName": "Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability",
  "shortDescription": "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.",
  "requiredAction": "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.",
  "dateAdded": "2026-09-21",
  "dueDate": "2026-09-24",
  "knownRansomware": false,
  "cwes": [
    "CWE-121"
  ],
  "notes": "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 ; ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-7273",
  "sources": [
    {
      "label": "NVD",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-7273"
    },
    {
      "label": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog"
    },
    {
      "label": "zyxel.com",
      "url": "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"
    },
    {
      "label": "cisa.gov",
      "url": "https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk"
    },
    {
      "label": "cisa.gov",
      "url": "https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk"
    },
    {
      "label": "nvd.nist.gov",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-7273"
    }
  ],
  "cvss": {
    "score": 8.8,
    "severity": "HIGH",
    "version": "3.1",
    "vector": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  },
  "epss": {
    "score": 0.02501,
    "percentile": 0.84195
  },
  "timeline": [
    {
      "date": "2026-09-21",
      "event": "Added to the CISA KEV catalog"
    },
    {
      "date": "2026-09-24",
      "event": "CISA remediation due date (BOD 22-01)"
    }
  ],
  "status": "past due"
}