// CVE

CVE-2026-88771

Critical 9.5 Exploited (KEV)

Citrix NetScaler ADC

9.5CVSS
82%EPSS
YesCISA KEV

Summary

Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This 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…

Published: 2026-09-27 · In KEV since: 2026-09-27

Analysis

🔴 Critical — actively exploited

Weakness: Improper Input Validation (CWE-20). Fails to validate input before using it.

How it's exploited: Exploitable over the network (internet-reachable), unauthenticated, no user interaction, and with low complexity.

⚠️ Critical combo: remote, unauthenticated and no interaction → trivial to automate.

Impact: Full compromise (confidentiality, integrity and availability).

Status: Active exploitation confirmed by CISA (KEV).

How to defend:
  • Patch now: it is in CISA's actively-exploited catalog (KEV), with a deadline.
  • Reduce exposure: keep it off the internet; firewall, VPN or network segmentation.
  • Detect: turn this CVE into detection rules.

CVSS vector

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

The vector encodes how it's exploited (translated above, in the analysis). Break it down in the CVSS tool →

← Back to the Threat Radar

Sources: CISA KEV · EPSS · FIRST.org · NVD. Analysis derived from the CVSS vector and exploitation status (no AI). Informational; always verify against the vendor's official advisory.