{"id":"CVE-2025-6543","aliases":["EUVD-2025-19085","GHSA-9gqr-6728-fpv3"],"status":"published","title":"Memory overflow vulnerability leading to unintended control flow and Denial of Service","description":"Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server","severity":{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.10433,"percentile":0.95797,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-119"],"published":"2025-06-25T12:49:57Z","modified":"2026-06-17T10:02:07Z","kev":{"date_added":"2025-06-30","due_date":"2025-07-21","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Unknown"},"exploitation":[{"source":"euvd","since":"2025-06-30"},{"source":"kev","since":"2025-06-30"}],"exploits":[{"source":"pocgithub","id":"grupooruss/Citrix-cve-2025-6543","title":"grupooruss/Citrix-cve-2025-6543","date":"2025-06-26","url":"https://github.com/grupooruss/Citrix-cve-2025-6543"},{"source":"pocgithub","id":"lex1010/CVE-2025-6543","title":"lex1010/CVE-2025-6543","date":"2025-06-30","url":"https://github.com/lex1010/CVE-2025-6543"},{"source":"pocgithub","id":"abrewer251/CVE-2025-6543_CitrixNetScaler_PoC","title":"abrewer251/CVE-2025-6543_CitrixNetScaler_PoC","date":"2025-07-03","url":"https://github.com/abrewer251/CVE-2025-6543_CitrixNetScaler_PoC"}],"products":[{"vendor":"citrix","product":"netscaler adc and gateway"},{"vendor":"citrix","product":"netscaler_application_delivery_controller"},{"vendor":"citrix","product":"netscaler_gateway"},{"vendor":"netscaler","product":"adc"},{"vendor":"netscaler","product":"gateway"}],"references":[{"url":"https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694788","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-6543","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-6543"},{"url":"https://github.com/advisories/GHSA-9gqr-6728-fpv3"}],"sources":{"cve":[{"id":"CVE-2025-6543","title":"Memory overflow vulnerability leading to unintended control flow and Denial of Service","description":"Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server","status":"published","published":"2025-06-25T12:49:57.896Z","modified":"2026-02-26T17:50:24.557Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L","level":"critical","assessor":"cna"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T14:32:40.419293Z"}],"euvd":[{"id":"EUVD-2025-19085","description":"Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server","status":"published","published":"2025-06-25T12:49:57Z","modified":"2026-02-26T17:50:24Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L","level":"critical"}],"exploited_since":"2025-06-30","updated_at":"2026-11-02T19:48:19.481461Z"}],"ghsa":[{"id":"GHSA-9gqr-6728-fpv3","title":"Memory overflow vulnerability leading to unintended control flow and Denial of Service in...","description":"Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server","status":"published","published":"2025-06-26T21:31:11Z","modified":"2025-10-22T00:34:22Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T15:04:09.266545Z"}],"kev":[{"id":"CVE-2025-6543","title":"Citrix NetScaler ADC and Gateway Buffer Overflow Vulnerability","description":"Citrix NetScaler ADC and Gateway contain a buffer overflow vulnerability leading to unintended control flow and Denial of Service. 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