CVE-2026-19490 — Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability

Impacted if

• NetScaler ADC ≤ 73.32 · ≤ 63.21
• NetScaler Gateway ≤ 73.32 · ≤ 63.21

Authentication bypass · over the network · no login

Vulnerability in NetScaler ADC and NetScaler Gateway.

CISA Known Exploited Vulnerabilities

Added on 2026-09-09, federal remediation due 2026-09-12. Citrix NetScaler ADC and NetScaler Gateway contain an authentication-bypass vulnerability involving an alternate path or channel. When the NetScaler appliance is configured as an AAA virtual server or as a Gateway (SSL VPN, ICA Proxy, CVPN, or RDP Proxy), an unauthenticated remote threat actor may be able to bypass authentication.

Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

First seen by AX-NEWS 04 Sep 2026, 15:25 UTC · latest story 13 Oct 2026, 00:00 UTC. Severity: NVD, or the CVE record while the NVD has not scored it. This product uses data from the NVD API but is not endorsed or certified by the NVD.