CVE-2026-100833 Contrast before 1.23.1 Image Substitution via Policy Generation
Attackers with Kata agent access can bypass image integrity checks to substitute malicious container images, compromising confidential computing guarantees.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-100833?
CVE-2026-100833 is a high-severity vulnerability in edgelesssys contrast, published on 27 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Contrast (edgelesssys/contrast) versions 1.14.0 before 1.23.1 generate runtime policies that fail to detect all container image substitutions. A bad rebase during a Kata Containers update accidentally introduced an `allow_storage` rule that accepts storage entries using the `image_guest_pull` driver without verifying the image digest. An attacker with access to the Kata agent API — for example, a Kubernetes cluster administrator in Contrast's threat model — can therefore substitute a container image with an exploit payload, provided the substituted image satisfies the remaining policy rules, undermining the confidential container's integrity guarantees.
Weakness: CWE-20
Which versions are affected by CVE-2026-100833?
How do I fix CVE-2026-100833?
No fix has been published for CVE-2026-100833 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-100833 being exploited?
There is no known exploitation of CVE-2026-100833 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-m2qg-wrxv-h898, GHSA-mjj6-px65-jq92.