CVE-2026-100704 Kyverno before 1.19.1 ImageValidatingPolicy Exception Bypass
Attackers can bypass image signature verification in Kyverno by exploiting a flaw in PolicyException handling, allowing unsigned images into the cluster.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-100704?
CVE-2026-100704 is a high-severity vulnerability in kyverno, published on 26 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Kyverno is a policy engine for Kubernetes. In versions 1.14.0 through 1.19.0, the ImageValidatingPolicy (policies.kyverno.io/v1beta1) evaluator never reads the spec.images and spec.allowedValues fields of a PolicyException. Any PolicyException whose policyRefs and matchConditions match a resource causes image signature verification to be skipped for the entire resource rather than only for the listed images or values, so an exception intended to exempt a single trusted image exempts every image on the matched resource(s). As a result, unsigned or untrusted images can be admitted to the cluster without signature verification. This differs from ValidatingPolicy, GeneratingPolicy, and MutatingPolicy, which treat the same field as a partial exemption. The issue is fixed in version 1.19.1.
Weakness: CWE-863
Which versions are affected by CVE-2026-100704?
1 open source package ship an affected version, including kyverno.
| Package | Affected | Fixed in |
|---|---|---|
kyverno Bitnami | From 1.14.0 | 1.19.1 |
How do I fix CVE-2026-100704?
Upgrade kyverno to 1.19.1 or later.
Is CVE-2026-100704 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100704 exists.
Sources
Also known as BIT-kyverno-2026-100704, GHSA-435c-9ffq-3prr, GHSA-5cjf-wwfg-pj4c, MINI-29jx-c3v6-3m72, MINI-2w89-g84p-q7rf, MINI-72mh-m64m-jqx7 and 7 more.