CVE-2026-19490
Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability
Exploited in the wild
This vulnerability is on the CISA Known Exploited Vulnerabilities list, added 2026-09-09. Federal due date: 2026-09-12.
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.
Impact
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.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| NetScaler | Gateway | Versions 14.1 ≤73.32, 13.1 ≤63.21 |
| NetScaler | ADC | Versions 13.1 ≤63.21, 14.1 ≤73.32 |
| Citrix | Netscaler Application Delivery Controller | from 13.1 before 13.1-37.277 from 13.1 before 13.1-63.21 from 14.1 before 14.1-73.32 from 14.1-66.68 through 14.1-73.32 |
| Citrix | Netscaler Gateway | from 13.1 before 13.1-63.21 from 14.1 before 14.1-73.32 |