CVE-2026-4342: A security issue was discovered in ingress-nginx where a combination of Ingress annotations can be used to inj

This month

HIGH 8.8WATCHLISTUPGRADE

CVE-2026-4342 is a high-severity flaw (CVSS 8.8) affecting nginx ingress controller. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.)

Why this priority

High severity
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	1.4% (top 27%)
CISA exploited list	No
Weakness	CWE-20
Published	2026-03-19
Last modified	2026-06-17

Publisher (CNA): Kubernetes · Vendor: kubernetes

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-19 22:16 UTCPublished CVE record published
2026-06-17 10:56 UTCUpdated Record last modified

kubernetes nginx ingress controller UPGRADE

Affected: < 1.13.9 · >= 1.14.0 and < 1.14.5 · 1.15.0

Fixed in: 1.13.9, 1.14.5

Safe to downgrade to: a release before 1.14.0

1. Check installed version

apt-cache policy nginx-ingress-controller || rpm -q nginx-ingress-controller || nginx-ingress-controller --version

2. UPGRADE to 1.13.9 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade nginx-ingress-controller

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nginx-ingress-controller

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 1.14.0 (Debian / Ubuntu)

apt-cache madison nginx-ingress-controller sudo apt install nginx-ingress-controller=<VERSION_BEFORE_1.14.0> sudo apt-mark hold nginx-ingress-controller

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list nginx-ingress-controller sudo dnf downgrade nginx-ingress-controller-<VERSION_BEFORE_1.14.0> sudo dnf versionlock add nginx-ingress-controller

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-4342?

nginx ingress controller: upgrade to 1.13.9, 1.14.5. Exact commands for each OS are on this page.

Is CVE-2026-4342 being exploited?

CVE-2026-4342 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-4342 affect?

CVE-2026-4342 affects nginx ingress controller. Severity is high (CVSS 8.8). 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 disclo

How urgent is CVE-2026-4342?

Priority 54/100. High severity; On your watchlist

Software pages

nginx vulnerabilities · Kubernetes vulnerabilities

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References

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