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TI-2026-74052 Aliases CVE-2026-91184GHSA-8rxj-rxx8-xj47

Configuration injection in NGINX Gateway Fabric via AuthenticationFilter

Priority MEDIUM 40CWE-76Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

NGINX Gateway Fabric from 2.4.0 before 2.8.0 renders the basic and JWT authentication settings of a namespaced AuthenticationFilter into the shared data-plane nginx.conf without escaping or validation. This is an improper neutralization of equivalent special elements (CWE-76). An authenticated attacker with low privileges who can attach an AuthenticationFilter to a route on a shared Gateway can craft a value that breaks out of the quoted directive and injects arbitrary NGINX directives into that Gateway's data-plane configuration. The impact is limited to the control plane, but it may allow reading co-located tenants' mounted secrets or hijacking other tenants' routes.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00482 41st percentileScored 2026-11-07
Fix Fixed NGINX Gateway Fabric (F5): 2.8.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
F5NGINX Gateway Fabric2.4.0 to before 2.8.02.8.0Patch availableCNA
  • NGINX Gateway Fabric VendorF5 Affected 2.4.0 to before 2.8.0 Fixed in 2.8.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:*——F5
  • cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:* Versions — — ·F5

Remediation

Upgrade NGINX Gateway Fabric to version 2.8.0 or later, which is the fixed version listed for F5 NGINX Gateway Fabric. The sources list no fixed version for NGINX Gateway Fabric 2.8.0 advisory ids beyond this version.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA NGINX Gateway Fabric (F5) Fixed in 2.8.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    F5 NGINX Gateway Fabric 2.8.0

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-74061 Authentication bypass in NGINX Gateway Fabric exposes TLS private keysPriority LOW 31
    Show all 2 records →

Timeline

  1. 2026-10-14 Threatist record created from CVE-2026-91184
  2. 2026-10-14 Alias added: GHSA-8rxj-rxx8-xj47
  3. 2026-10-15 CISA SSVC decision points changed
  4. 2026-10-15 Priority changed: MEDIUM → LOW
  5. 2026-10-16 Priority changed: LOW → MEDIUM

References

Advisory 1

  • TI-2023-25230 BIG-IP Configuration utility unauthenticated remote code execution vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-01269 Missing authentication in F5 BIG-IP KEVCVSS 3.1CRITICAL 9.8
  • TI-2021-05850 Memory corruption in BIG-IP KEVCVSS 3.1CRITICAL 9.8
  • TI-2021-05845 Server-side request forgery in BIG-IP; BIG-IQ KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-04820 Path traversal in BIG-IP KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
See all 1057 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences