ansible-core user module: unprivileged user can redirect a privileged run to create or own any file on the host

Impact

When a privileged playbook runs the user module against an unprivileged account's home directory, that account can cause the module to silently create or replace the contents of any file on any path and take ownership of it. If the attacker also has traversal permission on the containing directory, they keep write control of the file afterwards as its owner. On a fleet where Ansible runs as root to configure GPU nodes - driver pinning, cgroup limits, systemd units, SSH policy - one local user on one node can turn a routine user-management play into local root-equivalent control of a config file of their choosing. Exploitation needs the privileged run to happen, which is why Red Hat rates attack complexity high.

Who can reach it

A local, unprivileged user on a managed node who can modify their own home directory, combined with a privileged Ansible run that targets that account. No remote access needed; it depends on the operator executing the play.

What to do

Update ansible-core and the Automation Platform execution environments through the vendor errata (RHSA-2024:8969, 9894, 10762, RHSA-2025:1861). This is a control-node and execution-environment package update, not a managed-node change: rebuild or re-pull the execution environment images and restart the automation jobs that use them. Managed GPU nodes do not need to be drained or rebooted.

References

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