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

CISA Known Exploited Vulnerabilities

Name

Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability

Vendor

Citrix

Product

NetScaler

Added to the catalog

2026-09-09

Due date for US federal agencies

2026-09-12

Weaknesses

CWE-288

Catalog version

2026.10.30

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.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://support.citrix.com/external/article/CTX696939/netscaler-adc-and-netscaler-gateway-secu.html
• https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
• 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

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2026-08-19T13:17:45.000

Last modified

2026-10-26T13:10:00.140

Weaknesses

CWE-288

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.

References

• https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696939 (Vendor Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-19490 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:42:31.494Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-19490

CVE record

Title (CNA)

NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-19490

Assigner

NetScaler

State

PUBLISHED

Published

2026-08-19T12:54:39.730Z

Updated

2026-10-07T18:01:17.320Z

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.

References

• https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696939

Read on 2026-11-03T02:18:47.386Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/19xxx/CVE-2026-19490.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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