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TI-2026-40223 Aliases CVE-2026-55723GHSA-wxxq-mwhh-cvm2

NGINX Ingress Controller vulnerability

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 · Low
Fix status
Fixed

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

Summary

When NGINX Ingress Controller is configured with Custom Resource Definitions (CRDs) or Ingress annotations, an injection vulnerability exists in the configuration generator of NGINX Ingress Controller. Multiple user-controllable fields are written into the generated NGINX configuration without sanitization. An authenticated attacker with permission to create or modify these CRDs or annotations may craft values that inject arbitrary NGINX configuration directives. Impact: An authenticated attacker granted write access to NGINX Ingress Controller CRDs or Ingress annotations through the Kubernetes API may be able to inject arbitrary NGINX configuration directives, create or delete files, or disable services. 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 0.00509 43rd percentileScored 2026-11-07
Fix Fixed NGINX Ingress Controller (F5): 5.5.2, 2026-lts-r3

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 Ingress Controller5.0.0 to before 5.5.2; 2026-lts-r1 to before 2026-lts-r35.5.2, 2026-lts-r3Patch availableCNA
  • NGINX Ingress Controller VendorF5 Affected 5.0.0 to before 5.5.2; 2026-lts-r1 to before 2026-lts-r3 Fixed in 5.5.2, 2026-lts-r3 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*3.6.0 – 3.7.2; 4.0.0 – 4.0.1; 5.0.0 to before 5.5.2VulnerableF5
  • cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* Versions 3.6.0 – 3.7.2; 4.0.0 – 4.0.1; 5.0.0 to before 5.5.2 Vulnerable ·F5

Remediation

  • Fix · CNA NGINX Ingress Controller (F5) Fixed in 5.5.2, 2026-lts-r3

Fixed in the same release

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

  • Release ·

    F5 NGINX Ingress Controller 2026-lts-r3, 5.5.2

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-37967 NGINX Ingress Controller vulnerabilityPriority LOW 32
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-55723
  2. 2026-10-03 Alias added: GHSA-wxxq-mwhh-cvm2

References

Patch 1

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2026-31136 NGINX ngx_http_rewrite_module vulnerability CVSS 4.0CRITICAL 9.2
  • TI-2026-30813 NGINX Map directive and Regex matching vulnerability CVSS 4.0CRITICAL 9.2
  • TI-2026-08132 NGINX ngx_http_rewrite_module vulnerability CVSS 4.0CRITICAL 9.2
  • TI-2026-30812 NGINX Open-Source ngx_http_v3_module vulnerability CVSS 4.0CRITICAL 9.2
  • TI-2026-30432 NGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability CVSS 4.0CRITICAL 9.2
See all 24 →

Sources

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