CVE-2026-32682: NGINX Gateway Fabric vulnerability
When NGINX Gateway Fabric is configured using GRPCRoutes, an authenticated, remote attacker with permission to create or modify GRPCRoute resources can cause the NGINX Gateway Fabric control plane to terminate by sending undisclosed GRPCRoute configurations containing backendRef filters. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Metrics
- CVSS v4.0
- 7.1
- Severity
- HIGH
- Fixed in
- 2.6.4
- Affected Products
- 1
HarborGuard Analysis
Synopsis
This is an authenticated denial-of-service vulnerability in NGINX Gateway Fabric affecting versions 1.3.0 through 2.6.3. A remote attacker who holds a Kubernetes RBAC role permitting creation or modification of GRPCRoute resources can crash the Gateway Fabric control plane by submitting a crafted GRPCRoute configuration that includes backendRef filters. Successful exploitation shuts down the control plane, disrupting traffic routing for workloads managed by the gateway. A patched-image rebuild at version 2.6.4 is available on HarborGuard for affected environments.
HarborGuard Coverage
Detection of CVE-2026-32682 is available across every HarborGuard environment; the CVE is ingested from upstream feeds within minutes of publication and matched against customer images, including custom-built images that bundle NGINX Gateway Fabric. Coverage spans both registry scans and in-pipeline image checks at build time.
AvailableHarborGuard is capable of scoring this CVE at CVSS 7.1 HIGH and weighting that score against each environment's compliance policy to determine urgency. Triage results can be routed automatically to the team or inbox responsible for gateway infrastructure within each customer organization.
AvailableA patched-image rebuild pinned to NGINX Gateway Fabric 2.6.4 is available on HarborGuard for any environment running an affected version (1.3.0 through 2.6.3). For customers with auto-remediation enabled, HarborGuard rebuilds the image, runs a regression test suite, and opens a pull request against affected workloads automatically.
AvailableExploit Conditions
- Network reachabilityRequired
The attacker must reach the Kubernetes API server over the network to submit the malicious GRPCRoute resource.
- AuthenticationRequired
A low-privilege Kubernetes account with RBAC permission to create or modify GRPCRoute resources is sufficient; no admin credentials are needed.
- Victim interactionNot required
No human interaction is required; the control plane processes the malicious configuration automatically upon submission.
- Attack complexityDetail
The exploit is reliable and condition-free; no race conditions or special environmental factors are required to trigger the crash.
Blast Radius
- Crashes the NGINX Gateway Fabric control plane process, halting its ability to program NGINX data-plane instances.
- All traffic routing rules managed by the gateway stop being updated or enforced, disrupting ingress and east-west service traffic for dependent workloads.
- The outage persists until the control plane is restarted and may recur if the attacker retains GRPCRoute write access.
How HarborGuard Handles This
Available on HarborGuard: images containing NGINX Gateway Fabric versions 1.3.0 through 2.6.3 are matched against this CVE automatically within minutes of publication. For environments where the affected image is detected, a rebuild at version 2.6.4 is available. For customers with auto-remediation enabled, HarborGuard rebuilds the image, executes regression tests, and opens a pull request against affected workloads; median time from CVE publication to merged patch PR for high-severity issues is around 90 minutes in environments with auto-remediation enabled. Because this vulnerability requires only a low-privilege Kubernetes account, teams that cannot immediately upgrade should review RBAC policies to restrict GRPCRoute create and update permissions to the minimum necessary set of service accounts while the patch is applied.
Fix available
- F5 / NGINX Gateway Fabric< 2.6.4 (from 1.3.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N