{"id":"CVE-2026-88778","aliases":["EUVD-2026-87973","GHSA-mh3h-4j34-54mr"],"status":"published","title":"TCP Initial Sequence Number (ISN) prediction","description":"Predictable exact value from previous values 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.","severity":{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00694,"percentile":0.53361,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-342"],"published":"2026-09-27T16:43:16Z","modified":"2026-09-29T17:17:12Z","exploits":[{"source":"pocgithub","id":"CompleteTech-Security/netscaler-cve-2026-88778-check","title":"CompleteTech-Security/netscaler-cve-2026-88778-check","date":"2026-10-23","url":"https://github.com/CompleteTech-Security/netscaler-cve-2026-88778-check"}],"products":[{"vendor":"citrix","product":"netscaler_application_delivery_controller"},{"vendor":"citrix","product":"netscaler_gateway"},{"vendor":"citrix netscaler","product":"adc"},{"vendor":"citrix netscaler","product":"gateway"},{"vendor":"netscaler","product":"adc"},{"vendor":"netscaler","product":"gateway"}],"references":[{"url":"https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096","tags":["Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-88778"},{"url":"https://github.com/advisories/GHSA-mh3h-4j34-54mr"}],"sources":{"cve":[{"id":"CVE-2026-88778","title":"TCP Initial Sequence Number (ISN) prediction","description":"Predictable exact value from previous values 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.","status":"published","published":"2026-09-27T16:43:16.503Z","modified":"2026-09-29T16:35:06.769Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L","level":"high","assessor":"cna"}],"cwes":["CWE-342"],"updated_at":"2026-11-02T13:41:53.237769Z"}],"euvd":[{"id":"EUVD-2026-87973","description":"Predictable exact value from previous values 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.","status":"published","published":"2026-09-27T16:43:16Z","modified":"2026-09-29T16:35:06Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L","level":"high"}],"updated_at":"2026-11-02T17:27:51.995341Z"}],"ghsa":[{"id":"GHSA-mh3h-4j34-54mr","title":"Predictable exact value from previous values vulnerability in Citrix NetScaler ADC and Citrix...","description":"Predictable exact value from previous values 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.","status":"published","published":"2026-09-27T18:30:22Z","modified":"2026-09-28T18:31:19Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/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":"high"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-342"],"updated_at":"2026-11-02T15:12:32.639211Z"}],"nvd":[{"id":"CVE-2026-88778","description":"Predictable exact value from previous values 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.","status":"published","published":"2026-09-27T17:16:57.11Z","modified":"2026-09-29T17:17:12.02Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/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":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"}],"cwes":["CWE-342"],"updated_at":"2026-11-02T14:12:52.081323Z"}]}}