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synackyesterday at 8:46 PM4 repliesview on HN

If your container has setuid binaries and these modules are loaded, yes.


Replies

lights0123yesterday at 9:01 PM

With the exploits published as-is, you'll only get root inside the container: there's no explicit namespace break, and calling setuid() in a container just gives you root in the container.

However, it can be used to modify files that are passed into the container (e.g. Docker run -v), or files that are shared with other containers (e.g. other Docker containers sharing the same layers). kube-proxy with Kubernetes happens to share a trusted binary with containers by default, which is how it can be exploited: https://github.com/Percivalll/Copy-Fail-CVE-2026-31431-Kuber...

miduilyesterday at 9:09 PM

It's poisoning the filesystem cache, if you don't have a setuid binary handy you just poison anything else that gets executed by the host.

aaronmdjonestoday at 12:57 AM

You don't need any setuid binaries. You could just as easily use the vulnerability to add a job to crontab(5) that causes the cron daemon to run whatever you want as root.

awoimbeeyesterday at 9:30 PM

And your containers need to have specific capabilities enabled, which aren't by default on kubernetes and podman.

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