CVE-2026-19490
Auth Bypass in Citrix Netscaler Application Delivery Controller 13.1 – 13.1-37.277
Raw vector
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:XCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-19490 is a critical-severity Authentication Bypass Using an Alternate Path or Channel (CWE-288) vulnerability in Citrix Netscaler Application Delivery Controller. Its CVSS base score is 9.3 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Stealth (T1211); ranked in the top 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
The strongest mitigations our analysis identified map to AC-25 (Reference Monitor) and AC-3 (Access Enforcement) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-62395
Vulnerability Data
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.
- CWE(s)
- KEV Date Added
- 09 September 2026
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 7 hardening rules · 3 OS baselines
V6.4.3V6.6.1V12.1.3
Mitigating Controls (NIST 800-53 r5) AI
Requires a tamperproof, always-invoked reference monitor that structurally blocks bypass via any alternate path.
Enforces authorization checks on every logical access path, eliminating unauthenticated alternate channels.
Mandates unique identification and authentication for all organizational users, covering the primary authentication requirement.
Controls all external and key internal interfaces, reducing the chance of unauthenticated alternate channels.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Requiring authentication on every channel and path directly eliminates alternate-path bypasses.
Enforcing authorizations and least privilege across all access vectors prevents unauthenticated alternate paths.
Protecting networks and environments from unauthorized logical access blocks bypass via undocumented channels.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
A.5.15 only requires defining a topic-specific access control policy and determining requirements; it does not itself enforce, implement or configure any access rules that would stop an alternate unauthenticated path from being exploitable.
Access rights provisioning and review prevent bypass via unmonitored or alternate channels.