CVE-2026-91184 NGINX Gateway Fabric vulnerability
Authenticated attackers can inject NGINX directives via AuthenticationFilter CRDs to read secrets, perform SSRF, or hijack routes in shared gateways.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-91184?
CVE-2026-91184 is a high-severity code injection vulnerability in F5 NGINX Gateway Fabric, published on 14 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Description
NGINX Gateway Fabric has a vulnerability when it renders the spec.basic.realm (and spec.jwt.realm) field of a namespaced AuthenticationFilter verbatim, unescaped and unvalidated, into the shared data-plane nginx.conf as auth_basic "<realm>";. A namespaced authenticated attacker that configures AuthenticationFilter CRD to an HTTPRoute/GRPCRoute on a shared Gateway can craft a realm value that closes the quoted directive and the enclosing location {} block and injects arbitrary NGINX directives into that Gateway's data-plane config.
Impact
A remote authenticated attacker can send crafted requests to configure NGINX Gateway Fabric AuthenticationFilter CRD and may be able to read every co-located tenant's mounted secrets, SSRF via proxy_pass, reading the pod ServiceAccount token, or hijacking other tenants' routes. There is no data plane exposure; this is a control plane issue only.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Weakness: CWE-76
Which versions are affected by CVE-2026-91184?
1 open source package ship an affected version, including nginx-gateway-fabric.
| Package | Affected | Fixed in |
|---|---|---|
nginx-gateway-fabric Bitnami | From 2.4.0 | 2.8.0 |
How do I fix CVE-2026-91184?
Upgrade nginx-gateway-fabric to 2.8.0 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-91184 being exploited?
There is no known exploitation of CVE-2026-91184 in the wild and no public exploit code.
Sources
Also known as BIT-nginx-gateway-fabric-2026-91184, GHSA-8rxj-rxx8-xj47.