Privilege Escalation Vulnerability in Beta9 by Beam Cloud

CVE-2026-120306

What is CVE-2026-120306?

The Beta9 vulnerability arises from improper isolation during the execution of shell commands in tenant image definitions. This allows a tenant to potentially manipulate the worker container's filesystem, exposing sensitive components such as runc and buildah binaries, and the Kubernetes service account token. Due to the shared namespaces and privilege escalation capabilities, an attacker can leverage this flaw to gain unauthorized access to the worker environment. A fix was implemented in Beta9 worker version 0.1.756 to enhance security by enforcing OCI isolation and limiting namespace visibility.

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