CVE-2026-19490
KEV: known exploited SSVC: activeNetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-19490
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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
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
Attack conditions and impact
Derived from the NVD CVSS 3.1 vectorThis vulnerability may be exploitable over the internet without authentication or user interaction.
| Metric | Value | Meaning |
|---|---|---|
| Attack vector AV | N | Network |
| Attack complexity AC | L | Low (easy) |
| Privileges required PR | N | None |
| User interaction UI | N | None |
| Scope S | U | Unchanged |
| Confidentiality C | H | High |
| Integrity I | H | High |
| Availability A | H | High |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
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.
CISA KEV entry
Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability — Citrix / NetScaler
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.
https://support.citrix.com/external/article/CTX696939/netscaler-adc-and-netscaler-gateway-secu.html ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-19490
CVSS assessments
| Provider | Version | Score | Vector |
|---|---|---|---|
| NVD / 50a63c94-1ea7-4568-8c11-eb79e7c5a2b5 (Secondary) | 4.0 | 9.3 CRITICAL | 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 / [email protected] (Primary) | 3.1 | 9.8 CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA / NetScaler | 4.0 | 9.3 CRITICAL | 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 |
Affected products and packages
CNA (CVE.org)
| Vendor | Product | Versions |
|---|---|---|
| NetScaler | ADC | affected: 14.1 … <= 73.32 affected: 13.1 … <= 63.21 default: unaffected |
| NetScaler | Gateway | affected: 14.1 … <= 73.32 affected: 13.1 … <= 63.21 default: unaffected |
NVD CPE (7)
Show CPE list
| Vendor | Product | Range | CPE |
|---|---|---|---|
| citrix | netscaler_application_delivery_controller | >= 13.1, < 13.1-37.277 | cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* |
| citrix | netscaler_application_delivery_controller | >= 13.1, < 13.1-37.277 | cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:* |
| citrix | netscaler_application_delivery_controller | >= 13.1, < 13.1-63.21 | cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* |
| citrix | netscaler_application_delivery_controller | >= 14.1, < 14.1-73.32 | cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* |
| citrix | netscaler_application_delivery_controller | >= 14.1-66.68, <= 14.1-73.32 | cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* |
| citrix | netscaler_gateway | >= 13.1, < 13.1-63.21 | cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* |
| citrix | netscaler_gateway | >= 14.1, < 14.1-73.32 | cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* |
Linux distribution status
References (2)
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696939 NVD, CNA Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-19490 NVD, ADP CISA-ADP US Government Resourcegovernment-resource