{"basis":"claimed","id":"CVE-2026-88771","name":"Citrix NetScaler Improper Input Validation Vulnerability","vendorProject":"Citrix","product":"NetScaler","publishedAt":"2026-09-27","cvss":{"score":9.5,"severity":"CRITICAL","version":"4.0"},"exploited":{"kevAdded":"2026-09-27","dueDate":"2026-09-30","ransomware":false},"epss":{"score":0.8216,"percentile":0.99655,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"blocks","firstOn":"2026-10-01","daysToRule":4},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-10-21","daysToRule":24},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"title":"A remote code execution vulnerability exists due to improper input validation, which can allow an unauthenticated attacker to execute arbitrary commands","description":"Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway.\n\nThis issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to an unauthenticated attacker to execute arbitrary commands.","cwes":["CWE-20"],"vendors":[{"vendor":"cloudflare","status":"blocks","basis":"claimed","firstOn":"2026-10-01","firstIsNew":true,"daysToRule":4,"daysAtMost":null,"freePlan":false,"claims":[{"id":"a53b6d535b78e88d120a3896190c83b1e57eb2b6c7264933ccd3033f89f09dd0","cve_id":"CVE-2026-88771","vendor":"cloudflare","product":"Cloudflare Managed Ruleset","rule_id":"6802845374ea41a289fd4f43827ab216","rule_name":"Citrix Netscaler ADC and Gateway - Improper input validation - CVE:CVE-2026-88771","change":"new","default_action":"Block","published_on":"2026-10-01","source_url":"https://developers.cloudflare.com/changelog/post/2026-10-01-emergency-waf-release/","source_title":"WAF Release - 2026-10-01 - Emergency","excerpt":"Citrix Netscaler ADC and Gateway - Improper input validation - CVE:CVE-2026-88771. Previous action: N/A. New action: Block. This is a new detection.","first_seen_at":"2026-11-02T21:00:15.176Z"}]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-10-21","firstIsNew":true,"daysToRule":24,"daysAtMost":null,"freePlan":false,"claims":[{"id":"f4dedc75d034ac7ea7c98a398cb68f90f1b13073cdead0c55e1d709aa2dff9c9","cve_id":"CVE-2026-88771","vendor":"f5","product":"Attack signatures","rule_id":"200103695","rule_name":"Citrix Netscaler Remote Code Execution (2)","change":"new","default_action":null,"published_on":"2026-10-21","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200103695 \"Citrix Netscaler Remote Code Execution (2)\" (Command Execution, risk High), systems: Citrix. References: CVE-2026-88771.","first_seen_at":"2026-11-02T21:00:23.824Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-02T22:17:38.477Z","cvssVector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","ssvc":{"exploitation":"active","automatable":"yes","technicalImpact":"total"},"measured":[],"social":{"total":0,"first_seen":null,"daily":[{"day":"2026-10-20","posts":0},{"day":"2026-10-21","posts":0},{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0}],"top_posts":[],"exploit_repositories":[]}}