GHSA-f53h-mxv9-cp98 — high GitHub Advisory (CVE-2026-4342) in go/k8s.io/ingress-nginx

Description

A security issue was discovered in ingress-nginx where a combination of Ingress annotations 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.)

Basic information

Type: reviewed
Severity: high
Advisory on GitHub: Open advisory ↗
Repository advisory: —
Source code: Browse source ↗
Published (advisory): 2026-03-20 00:31:28 UTC
Updated: 2026-03-20 17:26:11 UTC
GitHub reviewed: 2026-03-20 17:26:08 UTC
NVD published: 2026-03-19 22:16:43 UTC

Score	Percentile
0.04%	11.32%

CVSS Scores

Base score	Version	Severity	Vector
8.8	3.1	—	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type	Value
GHSA	GHSA-f53h-mxv9-cp98 ↗
CVE	CVE-2026-4342 ↗

CWEs

CWE id	Name
CWE-20	Improper Input Validation

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
go	k8s.io/ingress-nginx	< 0.0.0-20260319175635-5183b7d86137	0.0.0-20260319175635-5183b7d86137	—

ingress-nginx comment-based nginx configuration injection