ingress-nginx controller - configuration injection via unsanitized auth-url annotationGHSA-fwwp-xcxw-39vq
HIGHGHSA-fwwp-xcxw-39vq is a high-severity (CVSS 8.8) Improper Input Validation vulnerability in k8s.io/ingress-nginx. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for k8s.io/ingress-nginx — see the affected versions and patch details below.
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-fwwp-xcxw-39vq.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
k8s.io/ingress-nginx🐹k8s.io/ingress-nginxReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
A security issue was discovered in ingress-nginx where the auth-url Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | k8s.io/ingress-nginx | all versions | 1.11.5go get k8s.io/ingress-nginx@v1.11.5 |
| 🐹Go | k8s.io/ingress-nginx | ≥ 1.12.0-beta.0&&< 1.12.1 | 1.12.1go get k8s.io/ingress-nginx@v1.12.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Ingress-NGINX Admission Controller v1.11.1 - FD Injection to RCE
by Beatriz Fresno Naumova · Feb 4, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for k8s.io/ingress-nginx, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update k8s.io/ingress-nginx to 1.11.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fwwp-xcxw-39vq is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How to detect GHSA-fwwp-xcxw-39vq
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id ghsa-fwwp-xcxw-39vq -u https://target- Template
- Ingress-Nginx Controller - Configuration Injection via Unsanitized `auth-url` Annotation
- Severity
- high
- Impact
- Authenticated users with Ingress creation permissions can inject nginx configuration through the auth-url annotation, leading to arbitrary code execution in the ingress-nginx controller context and disclosure of all Kubernetes Secrets cluster-wide.
- Remediation
- Upgrade to the patched version of ingress-nginx that properly sanitizes the auth-url annotation.
Template by ProjectDiscovery nuclei-templates (iamnoooob, rootxharsh, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is GHSA-fwwp-xcxw-39vq in your dependencies?
Find it across Go, including transitive dependencies.