CVE-2026-19490: Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability
Citrix · NetScaler
Listed by CISA as exploited in the wild since 9 Sep 2026. Below: exploitation status, EPSS and every published CVSS, each with its source, then affected versions and references.
Build snapshot collected · KEV catalog 2026.10.02 · EPSS of 2 Oct 2026 · not a live feed: collected once, at build time
Description
as written by CISA (KEV catalog)
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 KEV
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.
Affected products and versions
CVE record · NetScaler
NetScaler · ADC
- affected: from 14.1 through 73.32
- affected: from 13.1 through 63.21
NetScaler · Gateway
- affected: from 14.1 through 73.32
- affected: from 13.1 through 63.21
Status words (affected, unaffected, unknown) and version bounds are copied from the record. An upper bound such as “before 7.1.0” usually marks the first fixed version; confirm in the vendor advisory before planning an upgrade.
References
CISA KEV notes and CVE record
- 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
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696939
EPSS over the last 30 days
See also: all Citrix entries in KEV · the full KEV catalog
Related entries
Other Citrix entries in KEV
- CVE-2026-88772Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
- CVE-2026-88771Citrix NetScaler Improper Input Validation Vulnerability
- CVE-2026-8452Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
- CVE-2026-3055Citrix NetScaler Out-of-Bounds Read Vulnerability
- CVE-2025-7775Citrix NetScaler Memory Overflow Vulnerability
- CVE-2024-8069Citrix Session Recording Deserialization of Untrusted Data Vulnerability
Added in the same week (see the week)
- CVE-2026-84869ConnectWise ScreenConnect Improper Privilege Management and Missing Authorization Vulnerability
- CVE-2026-42016JFrog Artifactory Incorrect Authorization Vulnerability
- CVE-2026-42018JFrog Artifactory Improper Authentication Vulnerability
- CVE-2026-85706GitLab Community Edition and Enterprise Edition Path Traversal Vulnerability
- CVE-2026-86060MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Vulnerability
- CVE-2026-67277MikroTik RouterOS Missing Authentication for Critical Function Vulnerability
Questions about CVE-2026-19490
Is CVE-2026-19490 being exploited?
Yes, according to CISA. CVE-2026-19490 was added to the Known Exploited Vulnerabilities catalog on 9 Sep 2026, which CISA does only with reliable evidence of exploitation in the wild. The catalog field for ransomware campaign use says "Unknown".
What is the deadline to remediate CVE-2026-19490?
CISA set 12 Sep 2026 as the due date for US Federal Civilian Executive Branch agencies. The date is binding only for those agencies; other organisations can read it as a measure of urgency.
What is the EPSS score of CVE-2026-19490?
23.2%, in the 98th percentile, in the FIRST EPSS model of 2 Oct 2026. It estimates the probability of exploitation activity in the following 30 days. For a CVE already in KEV the score is secondary: exploitation has been observed.
How severe is CVE-2026-19490?
NVD rates it 9.8 CRITICAL (CVSS 3.1); 50a63c94-1ea7-4568-8c11-eb79e7c5a2b5 rates it 9.3 CRITICAL (CVSS 4.0). These are the published assessments as of 3 Oct 2026; this site does not rescore.
Which product does CVE-2026-19490 affect?
Citrix NetScaler, as named in the CISA catalog. The affected versions listed in the CVE record are on this page; the vendor advisory in the references is the authority on fixed versions.
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