CVE-2026-82429

/// Technical description

Description

The setuid-root `worker-launcher` binary adjusts ownership and permissions of worker directories by walking

the tree with FTS and calling `lchown` and `chmod` on each entry's full pathname while running with an

effective uid of 0. Both syscalls re-resolve the path at the time of the call, after FTS has classified the

entry, and the trees being walked are owned and writable by the untrusted topology user.

A tenant running code on a supervisor node could therefore replace an intermediate directory component with

a symbolic link between classification and the privileged operation, redirecting the root-owned `lchown` or

`chmod` at an arbitrary file on the host. The operation is repeatable at will, since crashing a worker

forces a relaunch and blob updates re-run the walk, so a failed attempt costs the attacker nothing.

This crosses the boundary that `supervisor.run.worker.as.user` and container isolation are intended to

enforce. It is the same defect class as the Hadoop cont

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References