CVE-2026-19490: Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability
Citrix NetScaler · in CISA KEV since 2026-09-09
- Kevscope CVE priority API 200 free calls a day, $5 for 2,000 calls (no expiry), or $19/month for 10,000: returns a patch-priority verdict for up to 20 CVEs per call with the evidence (KEV, EPSS, CVSS, CISA SSVC), most urgent first, by API or MCP.
- Kevscope API $5 pack $5 for 2,000 calls, never expires: patch-priority verdicts for up to 20 CVEs per call from today's KEV, EPSS, CVSS and SSVC data, by REST API or MCP. Pay by card, your API key is on screen the moment checkout ends; no account, no subscription.
- Exploited Vulnerabilities Brief: Weekly Edition $9/month: a fresh KEV + EPSS brief every Monday (PDF + CSVs): new exploited CVEs, what to patch first, upcoming CISA deadlines.
- All Three Monday Briefs: Rates, Recalls + Exploited Vulns $25/month: all three weekly briefs (Treasury/BLS rates & macro, NHTSA recalls, CISA KEV/EPSS) for $25/month instead of $37.
Secure Stripe checkout (card, Apple Pay, Google Pay) · 14-day fix-or-refund if it doesn't work as described · terms
What it is
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 (CISA)
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.
| CWE | CWE-288 |
|---|---|
| CVSS vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/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 |
| NVD published | 2026-08-19 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2026-19490.json · all KEV CVEs
🔔 Get a browser alert when CISA adds a new KEV entry (free, no email, one click to stop).
Get the full file: Exploited Vulnerabilities Brief: Weekly Edition ($9/month): each week's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.