Bulletin ID: HCSEC-2026-14
Affected Products / Versions: Nomad Community Edition from 0.9 up to 2.0.0, fixed in 2.0.1; Nomad Enterprise from 0.9 up to 2.0.0, fixed in 2.0.1, 1.11.5, and 1.10.11.
Publication Date: May 12, 2026
Summary
HashiCorp Nomad and Nomad Enterprise prior to 2.0.1 are vulnerable to arbitrary file read and write on the client host as the Nomad process user through a symlink attack. This vulnerability (CVE-2026-6959) is fixed in Nomad 2.0.1, 1.11.5 and 1.10.11.
Background
Nomad workloads are run by task drivers that implement various levels of filesystem isolation from the Nomad client host. Tasks within a workload allocation share a directory where logs are written. This directory is typically a bind mount from the host’s filesystem that contains the log files and named pipes that capture stdout and stderr from the workload.
Details
An attacker with permission to launch a malicious Nomad task may be able to manipulate the named pipe symlinks for an allocation’s log file, allowing read/write access to the Nomad host’s filesystem with the privileges of the Nomad process user.
Remediation
Customers should evaluate the risk associated with this issue and consider upgrading to Nomad 2.0.1, 1.11.5, 1.10.11, or newer.
Acknowledgement
This issue was identified by Alex Manson (Aiven / NeuroWinter)
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