{"cve":{"cve_id":"CVE-2026-7273","is_kev":true,"kev_date_added":"2026-09-21","kev_vendor_project":"Zyxel","kev_product":"GS1900 Series Switches","kev_vulnerability_name":"Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability","kev_short_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.","kev_required_action":"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.","kev_due_date":"2026-09-24","kev_known_ransomware":false,"kev_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","kev_cwes":["CWE-121"],"epss_score":0.02501,"epss_percentile":0.84421,"epss_as_of":"2026-10-15","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 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request.","published_at":"2026-06-16T02:20:29.847000Z","last_modified_at":"2026-09-22T12:10:51.067000Z","cvss_v3_score":8.8,"cvss_v3_vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"none","ssvc_automatable":false,"ssvc_technical_impact":"total","cwes":["CWE-121"],"nvd_references":["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"],"vuln_status":"Analyzed","trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-09-23T00:32:41.662445Z"},"effective_severity":"HIGH","badges":["kev","news"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack 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vulnerability, tracked as CVE-2026-7273 (CVSS score: 8.8), is a stack-based buffer overflow vulnerability that could result in arbitrary operating","thumbnail_url":"https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjj9eouOxeSvnYBzl5A8tWvEQ4w_CCx94YcFmpBAXXqHWNqvFBWj4vOgeZdHYAf0MU-chY63biCpHDnzRC0pwR7s3pTdQAWwPAVI-olRZuBwG0ilgAxnIY_1KofE3cpuA8lKOE01U26EFHYE_nLrXYXOWl47G1KaoFTZ5UOO81Cw0Kb20pFSfAc1b9i9E_K/s1600/veeam.jpg","author":"info@thehackernews.com (The Hacker News)","published_at":"2026-09-22T05:31:59Z","fetched_at":"2026-09-22T07:16:11.907695Z","trending_score":8.182933649949222e-6,"cve_ids":["CVE-2026-7273"]}],"references":[{"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","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2026-06-16T02:20:29.847000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:56:12.360668Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:56:12.360668Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:56:12.360668Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T23:46:59.033383Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cisa_reported","at":"2026-09-21T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"first_article","at":"2026-09-22T05:31:59Z","label":"First news coverage","source":"The Hacker News"}]}