Quick answers
- Is CVE-2026-124440 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-124440 being exploited in the wild.
- How severe is CVE-2026-124440?
- Critical severity, with a CVSS score of 9.9, published 8 November 2026.
- Which products and versions are affected?
- Kyverno 1.19.1.
- Is there a fix for CVE-2026-124440?
- Yes: fixed in 1.19.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-124440 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-124440?
- Check whether you run Kyverno at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 1.19.2
Technical details
The vulnerability is an authorization bypass in the apiCall namespace clamp introduced in v1.19.1. The clamp validates a decoded and cleaned path (url.PathUnescape and path.Clean) but issues the actual request against the raw, unmodified urlPath. By appending a malformed percent-escape such as ?a=% to the urlPath, an attacker forces url.PathUnescape to fail, causing the clamp to validate one path while the Kubernetes API server routes the request to a different namespace or cluster-scoped resource. The apiCall runs as the admission-controller ServiceAccount, allowing the attacker to read arbitrary namespaces and create mutating webhooks for cluster-admin escalation.
Affected products
- Kyverno Kyverno 1.19.1
Timeline
- 2026-10-23: disclosed
- 2026-11-08: advisory