CVE-2026-92768: Cockpit-Machines Information Disclosure

CVE-2026-92768 Overview

CVE-2026-92768 is an information disclosure vulnerability in cockpit-machines, the virtual machine management module for the Cockpit web-based server administration interface. The component passes password values directly as command-line arguments during VM creation or installation. Any local user who can read process metadata on the host can inspect these arguments and recover plaintext VM credentials. The flaw is tracked under CWE-214: Invocation of Process Using Visible Sensitive Information and requires only low-privileged local access to exploit.

Critical Impact
A local, authenticated user can harvest plaintext virtual machine passwords by reading /proc/<pid>/cmdline, leading to unauthorized access to provisioned VMs.

Affected Products

cockpit-machines component of the Cockpit management interface
Red Hat Enterprise Linux distributions shipping cockpit-machines (see Red Hat CVE-2026-92768 Advisory)
Downstream Linux distributions packaging the affected cockpit-machines release

Discovery Timeline

2026-09-18 - CVE-2026-92768 published to NVD
2026-09-22 - Last updated in NVD database

Technical Details for CVE-2026-92768

Vulnerability Analysis

The cockpit-machines module orchestrates VM lifecycle operations by invoking backend utilities such as virt-install and related libvirt tooling. During VM creation or guest OS installation, the component supplies user-provided credentials, including the root password or guest account password, as literal arguments on the child process command line.

On Linux systems, process arguments are exposed through /proc/<pid>/cmdline and enumerable via standard tools such as ps, top, and /proc walkers. By default, this pseudo-file is world-readable, so any unprivileged user on the host can observe the arguments of processes owned by other users during the window that the provisioning process runs.

Because the credential appears verbatim in the argument vector, an attacker does not need to intercept memory, hook syscalls, or escalate privileges. Polling /proc at short intervals is sufficient to capture the password before the process exits.

Root Cause

The root cause is insecure parameter passing. Sensitive material should be delivered to child processes through file descriptors, environment variables scoped to the child, or stdin, rather than through argv. The cockpit-machines code path constructs the invocation with the password interpolated into the argument list, exposing it to any observer with read access to the process table.

Attack Vector

Exploitation requires local access with a valid, low-privilege account on the Cockpit host. The attacker monitors the process table while an administrator provisions a new VM through the Cockpit web UI. When the backend invocation appears, the attacker reads its command-line arguments and extracts the password. No user interaction with the attacker is required, and no scope change occurs, but the disclosed credential can grant subsequent access to the newly created VM.

No verified proof-of-concept code has been published. Refer to the Red Hat Bug Report #2469258 for upstream discussion of the flaw.

Detection Methods for CVE-2026-92768

Indicators of Compromise

Unexpected read access to /proc/<pid>/cmdline for processes owned by root or the Cockpit service account by unprivileged users.
Long-running or high-frequency invocations of ps, cat /proc/*/cmdline, or custom /proc scanners from non-administrative accounts.
Successful VM console or SSH logins using credentials that were only ever entered through the Cockpit provisioning UI.

Detection Strategies

Audit process execution telemetry for virt-install or related libvirt commands where password flags appear in the argument vector.
Correlate Cockpit provisioning events with subsequent /proc enumeration activity from non-root sessions within the same time window.
Alert on shell one-liners or scripts that iterate /proc/*/cmdline on multi-user hosts.

Monitoring Recommendations

Enable Linux auditd rules covering execve and file reads under /proc/*/cmdline for accounts outside the administrative group.
Ship process command-line telemetry to a central data lake for retrospective hunting against argument patterns containing --password, --root-password, or similar flags.
Review Cockpit access logs to correlate VM creation activity with the set of interactive users present on the host at that moment.

How to Mitigate CVE-2026-92768

Immediate Actions Required

Apply vendor updates for cockpit-machines as soon as they are available from your distribution.
Restrict interactive shell access on Cockpit hosts to administrators who already possess equivalent privileges.
Rotate any VM credentials that were provisioned through Cockpit on multi-user hosts prior to patching.

Patch Information

Monitor the Red Hat CVE-2026-92768 Advisory for fixed package versions and errata identifiers. Downstream distributions will publish corresponding cockpit-machines updates that transition credential passing away from command-line arguments.

Workarounds

Mount /proc with the hidepid=2 option so that users cannot see process metadata for processes they do not own.
Limit Cockpit host accounts to administrators only, eliminating the local observer required for exploitation.
Provision VMs using SSH key injection or cloud-init user-data files rather than password-based flows exposed through the Cockpit UI.

bash

# Restrict /proc visibility so users only see their own processes
# Add to /etc/fstab and remount, or apply at runtime:
mount -o remount,rw,hidepid=2,gid=proc /proc

# Verify the option is active
mount | grep '/proc '