CVE-2026-19490
Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability
Citrix NetScaler
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.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 9 September 2026. US federal agencies were required to remediate it by 12 September 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 5.6%, which is higher than 92.5% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-19490 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-19490.
What does CVE-2026-19490 affect?
CVE-2026-19490 affects Citrix NetScaler. 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.
How severe is CVE-2026-19490?
CVE-2026-19490 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 5.6%, higher than 92.5% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 12 September 2026.
How should organisations respond to CVE-2026-19490?
Apply the vendor patch for Citrix NetScaler as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.