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

- Exploited (CISA KEV): yes, added 2026-09-09
- Published: 2026-08-19
- CVSS: 9.3 CRITICAL (v4.0)
- EPSS: 32.7% (98th percentile)
- CWE: 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.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | No public claim | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | No public claim | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2026-09-16 | 28 |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### F5

- 2026-09-16 · new · rule 200013220
  > Added: signature 200013220 "Citrix NetScaler Authentication Bypass" (Authentication/Authorization Attacks, risk High), systems: Citrix. References: CVE-2026-19490.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2026-19490 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2026-19490