NGINX Ingress Controller vulnerability (F5 NGINX Ingress Controller)

CVE-2026-55723
HIGH 8.7

At a glance

Source
NVD
EPSS
EPSS 0.51 % · percentile 43 ()
State
PUBLISHED
Published
Updated
Assigner
f5
NVD status
Analyzed

Description

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.

Weaknesses (CWE)

  • CWE-76 — Improper Neutralization of Equivalent Special Elements

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.3CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Lf5
CVSS 4.0HIGH 8.7CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:Nf5
CVSS 4.0HIGH 8.7CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · f5sirt@f5.com (Secondary)
CVSS 3.1HIGH 8.3CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:LNVD · f5sirt@f5.com (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
F5 · NGINX Ingress Controlleraffected 5.0.0 < 5.5.2 ; affected 2026-lts-r1 < 2026-lts-r3

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD