On 2026-09-09, CISA added CVE-2026-19490 (Citrix NetScaler) to its Known Exploited Vulnerabilities (KEV) Catalog [2]. The vulnerability is listed in the catalog as "Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability" [2]. CISA requires remediation in accordance with vendor mitigation instructions; see the original text in the body for specific requirements [2].
Backfill: this event became public on Sep 9, 2026 and we added it on Nov 10, 2026. It is not a new event.
CISA Adds Citrix NetScaler Vulnerability CVE-2026-19490 to Known Exploited Vulnerabilities Catalog
1 min read
- Disclosed
- Sep 9, 2026
- Published
- Nov 10, 2026
- Last updated
- Nov 8, 2026
- CVSS basis
- Our assessment
- 33.3%, higher than 98% of CVEs
- Exploitation and patch status
- ExploitedKEV
- Attack vector
- Vulnerability status
- Actor type
- Motivation
On this page
30-second summary
What happened
Who is affected
Industries mainly affected: Government, Cross-industry
What to do nowOur advice
CISA requires remediation in accordance with vendor mitigation instructions; see the original text in the body for specific requirements [2]
Timeline
Technical details
CISA KEV Listing Record
On 2026-09-09, CISA added CVE-2026-19490 to the catalog for Citrix NetScaler [2].
Original Technical Description
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 , ICA Proxy, CVPN, or RDP Proxy), an unauthenticated remote threat actor may be able to bypass authentication. [2]
Official Requirements
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. [2]
Individual Vulnerability Record
The U.S. National Vulnerability Database (NVD) provides an independent vulnerability record and description for CVE-2026-19490. [1]
References
Official / primary3
- [1]
“Vulnerability in NetScaler ADC and NetScaler Gateway. This issue affects ADC: from 14.1 through 73.32 and from 13.1 through 63.21; Gateway: from 14.1 through 73.32 and from 13.1 through 63.21.”
- [2]
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