CVE-2026-51083 Proxmox CVE debrief

Who should care

Users of Proxmox Virtual Environment (PVE) 9.x and 8.x should be aware of this vulnerability and take necessary actions to mitigate the risk. The vulnerability has a high impact on the confidentiality of the system, as it allows unauthorized access to sensitive information. System administrators and security teams should review the official advisory and take necessary actions to protect their systems.

Technical summary

The vulnerability is caused by incorrect access control in Proxmox Virtual Environment (PVE) 9.x qemu-server before 9.1.8 and 8.x before 8.4.8. This allows users with limited privileges to obtain hashed passwords via the cloudinit/dump API. The vulnerability has a high impact on the confidentiality of the system, as it allows unauthorized access to sensitive information. The cloudinit/dump API does not properly validate user permissions, allowing users with limited privileges to access sensitive information.

Defensive priority

High

Recommended defensive actions

• Update Proxmox Virtual Environment (PVE) to version 9.1.8 or later, or 8.4.8 or later.
• Restrict access to the cloudinit/dump API.
• Monitor for suspicious activity related to the cloudinit/dump API.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record was published on 2026-07-17T15:16:46.973Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the vendor. The CVE record does not provide detailed information about the vulnerability, so defenders should review the official advisory for more information.

Official resources