CVE-2026-57231: Podman: Malformed Image can trick podman run into leaking host environment variables into the container

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-26 · updated 2026-10-25
Weakness: CWE-200

Description

Podman is a tool for managing OCI containers and pods. From 1.8.1 until 5.8.4, a container image that contains a environment variable with just a key and no value can trick podman into passing that variable from the host into the container. This is made worse by the fact that using an asterisk (*) will cause podman to pass all host variables into the container. So essentially a malicious image can exfiltrate all podman environment variables that are set in the session from where the container is launched. This vulnerability is fixed in 5.8.4 and 6.0.0.

Affected products

podman: from 1.8.1 before 5.8.4; 6.0.0-rc1 — fixed in 5.8.4

How to fix

Upgrade to a fixed version: podman 5.8.4. Check the vendor advisory for mitigations.

References

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