CVE-2026-51082

Severity CVSS v4.0:

Pending analysis

Type:

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Publication date:

17/07/2026

Last modified:

17/07/2026

Description

A race condition between the vncproxy and vncwebsocket API calls in Proxmox Virtual Environment (PVE) 9.x pve-manager before 9.1.9 and 8.x before 8.4.19; qemu-server 9.x before 9.1.7 and 8.x before 8.4.7; and pve-container before 6.1.3 (PVE 9.x) and before 5.3.4 (PVE 8.x) allows an attacker with privileges to call "vncproxy" to hijack a VNC session that is established in parallel by a different user for a different VM.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.20 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): High
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

7.20

Severity 3.x

HIGH

References to Advisories, Solutions, and Tools

https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/post-849971