{"id":"CVE-2023-6549","aliases":["EUVD-2023-58779","GHSA-8fxh-p33g-qf5m"],"status":"published","title":"Denial of Service","description":"Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read","severity":{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.57633,"percentile":0.99088,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":false,"fix_available":false},"cwes":["CWE-119"],"published":"2024-01-17T20:15:53Z","modified":"2026-06-17T06:50:58Z","kev":{"date_added":"2024-01-17","due_date":"2024-02-07","required_action":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Unknown"},"exploitation":[{"source":"euvd","since":"2024-01-17"},{"source":"kev","since":"2024-01-17"}],"exploits":[{"source":"nuclei","id":"CVE-2023-6549","title":"Citrix Netscaler ADC \u0026 Gateway - Out-Of-Bounds Memory Read","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-6549.yaml"}],"products":[{"vendor":"citrix","product":"netscaler adc"},{"vendor":"citrix","product":"netscaler adc and netscaler gateway"},{"vendor":"citrix","product":"netscaler_application_delivery_controller"},{"vendor":"citrix","product":"netscaler_gateway"},{"vendor":"cloud software group","product":"netscaler adc"}],"references":[{"url":"https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549","tags":["x_transferred","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-6549","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-6549"},{"url":"https://github.com/advisories/GHSA-8fxh-p33g-qf5m"}],"sources":{"cve":[{"id":"CVE-2023-6549","description":"Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read","status":"published","published":"2024-01-17T20:15:53.345Z","modified":"2025-10-21T23:05:27.936Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T14:35:25.095989Z"}],"euvd":[{"id":"EUVD-2023-58779","description":"Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read","status":"published","published":"2024-01-17T20:15:53Z","modified":"2025-10-21T23:05:27Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"exploited_since":"2024-01-17","updated_at":"2026-11-02T20:31:27.312976Z"}],"ghsa":[{"id":"GHSA-8fxh-p33g-qf5m","title":"Denial of Service","description":"Denial of Service","status":"published","published":"2024-01-17T21:30:21Z","modified":"2025-10-22T00:32:59Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T15:04:07.112106Z"}],"kev":[{"id":"CVE-2023-6549","title":"Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability","description":"Citrix NetScaler ADC and NetScaler Gateway contain a buffer overflow vulnerability that allows for a denial-of-service when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server.","cwes":["CWE-119"],"kev":{"date_added":"2024-01-17","due_date":"2024-02-07","required_action":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Unknown"},"updated_at":"2026-11-02T17:00:16.234141Z"}],"nvd":[{"id":"CVE-2023-6549","description":"Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read","status":"published","published":"2024-01-17T21:15:11.69Z","modified":"2026-06-17T06:50:58.16Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T14:09:01.900189Z"}]}}