CVE-2026-92768: 
Linux Debian vulnerability analysis and mitigation

CVE-2026-92768 is an information disclosure vulnerability in cockpit-machines, a component of Red Hat Enterprise Linux used to manage virtual machines via the Cockpit web interface. The flaw allows a local attacker to expose sensitive VM credentials — including plaintext passwords — by inspecting process command-line arguments during VM creation or installation operations. It was reported on May 11, 2026, publicly disclosed on September 18, 2026, and affects cockpit-machines-348-1.el10 and related versions on Red Hat Enterprise Linux. It carries a CVSS v3.1 base score of 5.5 (Medium) (Red Hat CVE, GitHub Advisory).

The root cause is classified as CWE-214 (Invocation of Process Using Visible Sensitive Information): cockpit-machines passes password values directly as command-line arguments when spawning child processes during VM provisioning. Specifically, in src/libvirtApi/domain.ts, plaintext passwords are passed to openssl passwd -5 <password> on the command line, and a JSON payload containing rootPassword and/or userPassword is passed as sys.argv[1] to src/scripts/install_machine.py. On systems where /proc visibility is not restricted (i.e., without hidepid=2), any local user can read these arguments via ps -ef or by reading /proc/<pid>/cmdline. Exploitation requires local access, a low-privilege account, and a narrow time window during which the VM creation or installation workflow is actively running (Red Hat Bugzilla, Red Hat CVE).

Successful exploitation results in full disclosure of VM credentials — including rootPassword and userPassword in plaintext — to other local users on the same host. There is no integrity or availability impact; the vulnerability is purely a confidentiality issue. However, the disclosed credentials can enable an attacker to gain unauthorized access to provisioned virtual machines, potentially enabling lateral movement within a virtualized environment (Red Hat CVE, Red Hat Bugzilla).

No public proof-of-concept exploit code or exploit kits have been identified, and there is no evidence of in-the-wild exploitation as of the disclosure date. The EPSS score is 0.0, indicating very low probability of near-term exploitation, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation is constrained to local access with a narrow time window during VM provisioning operations, and systems with /proc mounted using hidepid=2 are materially protected (Red Hat Bugzilla, GitHub Advisory).

1. Gain local access: Obtain a low-privilege local account on a host running cockpit-machines (e.g., cockpit-machines-348-1.el10) where /proc is not mounted with hidepid=2 or equivalent restrictions.
2. Wait for VM provisioning: Monitor or wait for an administrator to initiate a VM creation or installation operation via the Cockpit web interface that includes rootPassword and/or userPassword.
3. Enumerate candidate processes: From the unprivileged account, run ps -ef | grep -E 'openssl passwd|-c $@|install_machine.py|python3' to identify relevant child processes spawned by cockpit-machines.
4. Read command-line arguments: For each identified process PID, execute tr '\0' ' ' < /proc/<pid>/cmdline to read the full command line, which will contain either openssl passwd -5 <plaintext_password> or a JSON string including rootPassword and/or userPassword.
5. Extract credentials: Parse the output to obtain the plaintext VM passwords, then use them to authenticate to the provisioned virtual machine (Red Hat Bugzilla).

• Process: Unexpected ps or cat /proc/*/cmdline commands executed by low-privilege users during VM provisioning windows; unusual access to /proc/<pid>/cmdline for cockpit or python3 processes from non-root accounts.
• Logs: Audit log entries (via auditd) showing low-privilege users reading /proc/<pid>/cmdline for processes owned by the cockpit service account during VM creation or installation timeframes.
• Network: Subsequent unauthorized SSH or console login attempts to newly provisioned VMs from unexpected source accounts or IPs, potentially indicating credential use after disclosure (Red Hat Bugzilla).

The proposed fix is to stop passing secrets as command-line arguments: feed passwords to openssl via standard input using the -stdin flag, and pass the JSON payload to install_machine.py via stdin rather than sys.argv[1]. As an immediate workaround, mount /proc with hidepid=2 (or hidepid=invisible on newer kernels) to prevent unprivileged users from reading other processes' command-line arguments. Additionally, avoid performing VM provisioning with sensitive passwords on shared multi-user hosts until a patched package is released. Monitor the Red Hat advisory page for an updated cockpit-machines package (Red Hat CVE, Red Hat Bugzilla).

The vulnerability was discovered by Aisle Research in partnership with Red Hat and reported responsibly without embargo, given its local-only nature and the availability of practical mitigations. Red Hat classified the issue as Moderate impact, consistent with its local-access requirement and the existence of configuration-level mitigations. No significant broader media coverage or notable community commentary has been identified beyond the standard advisory and database entries (Red Hat CVE, Red Hat Bugzilla).