Called exploited 15 days after disclosure.
Measured from the CVE publication date to the earliest of 3 KEV catalogues that list it.
The life of this vulnerability
- CVE published
- First KEV listing15d
- Last KEV listing6d
- Last sighting6d
Gaps are compressed to equal steps. The elapsed time is printed under each.
Which catalogues call it exploited
- CISA KEVUS federallisted Sep 9, 2026
- EUVDENISA, European Unionlisted Sep 9, 2026
- VulnCheck KEVcommercial researchlisted Sep 3, 2026
- CIRCLaggregator, mirrors the abovelisted Sep 3, 2026, not counted
3 catalogues list it. CIRCL aggregates the others and is shown but not counted.
Public exploitation evidence
- reported exploitationprevidian.com/CVE-2026-19490
1 public report collected from VulnCheck and CIRCL, first on Sep 3, 2026. Each links to its original source. We have not verified them.
Description
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.
