Copy Fail exploit (CVE-2026-31431) allows unprivileged users to gain root shell in Linux containers
By
Gabriel Garrido
23d ago· 18 min readenNews
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Summary
A security vulnerability (CVE-2026-31431) called "Copy Fail" was publicly disclosed on April 29th, 2026. The exploit allows a local unprivileged user to obtain a root shell by running a Python script. It affects Linux containers used for public-facing services, development environments, and CI jobs. The author notes they moved from Docker to Podman about a year ago, and this CVE is particularly interesting in that context.
Key quotes
· 3 pulledThis vulnerability allows a local unprivileged user to obtain a root shell by running the Python script shared by the author.
A container exploited with Copy Fail can used quite effectively for many kinds of attacks.
This CVE is quite interesting to me as it's been about a year since I moved away from Docker to Podman
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