CVE-2026-100833: Contrast before 1.23.1 Image Substitution via Policy Generation

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-27 · updated 2026-10-09
Weakness: CWE-20

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.

Affected products

edgelesssys contrast: from 1.14.0 before 1.23.1 — fixed in 1.23.1

How to fix

Upgrade to a fixed version: edgelesssys contrast 1.23.1. Check the vendor advisory for mitigations.

References

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