Linux kernel (overlayfs, Ubuntu patch): OverlayFS file-capability privilege escalation

Impact

OverlayFS file-capability privilege escalation; trivially weaponised inside unprivileged user namespaces [KEV]

Who can reach it

Any tenant process in a container

What to do

Ubuntu-specific patch delta. Livepatchable on Ubuntu Pro Livepatch; otherwise drain + reboot

References

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