Executive brief
HashiCorp Nomad is a tool used to manage and deploy applications across data centers. A security flaw in its Docker task driver allows users with job submission privileges to bypass security restrictions and access files on the underlying host server. This could lead to the unauthorized reading or modification of sensitive system files, potentially compromising the entire server hosting the application.
Technical details
A sandbox escape vulnerability exists in the HashiCorp Nomad Docker task driver due to improper link resolution (CWE-59). The driver's containment check fails to fully account for symbolic links when validating bind mounts, allowing a mount that resolves outside the intended allocation directory. An authenticated attacker with job submission privileges (or any API client if ACLs are disabled) can exploit this to bind-mount arbitrary host paths into a container. This allows for reading and writing files on the host filesystem even when volume bind mounts are explicitly disabled. The issue is fixed in Nomad 2.0.4 and Nomad Enterprise 2.0.4, 1.11.8, and 1.10.14.
Affected products
- HashiCorp Nomad 0.4.1 to 2.0.3
- HashiCorp Nomad Enterprise 0.4.1 to 2.0.3; 1.11.0 to 1.11.7; 1.10.0 to 1.10.13
Timeline
- 2026-07-08: disclosed
- 2026-07-08: patched
- 2026-07-08: advisory