CVE-2026-13474 Denial of service via malformed HTTP/2 requests
Attackers can cause denial of service via malformed HTTP/2 requests on NetScaler devices if HTTP/2 is enabled in the profile.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-13474?
CVE-2026-13474 is a high-severity denial of service vulnerability in NetScaler ADC, published on 30 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Denial of service via malformed HTTP/2 requests in NetScaler ADC and NetScaler Gateway if HTTP/2 is enabled in HTTP Profile and associated with the virtual server (of type LB, CS, VPN) or the service configured on NetScaler
Weakness: CWE-401
Which versions are affected by CVE-2026-13474?
It affects 2 products.
Products include Citrix NetScaler ADC, Citrix Netscaler Gateway.
How do I fix CVE-2026-13474?
No fix has been published for CVE-2026-13474 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-13474 being exploited?
There is no known exploitation of CVE-2026-13474 in the wild and no public exploit code.
Other vulnerabilities in NetScaler ADC
- CVE-2023-3519 Citrix NetScaler ADC and NetScaler Gateway Code Injection
- CVE-2026-88771 Citrix NetScaler Improper Input Validation
- CVE-2026-88772 Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer
- CVE-2023-4966 Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow
- CVE-2026-19490 Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel
Sources
Also known as GHSA-256v-mmj4-qqjc.