# CVE-2026-51082: Proxmox Virtual Environment race condition in VNC session handling

Source: https://junglewise.ai/threats/cve-2026-51082-proxmox-virtual-environment-race-condition-in-vnc-session  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-17. Updated: 2026-07-17  
License: CC BY 4.0 with a link back

CVE-2026-51082 · Severity: info · Published 2026-07-17

A security flaw in Proxmox Virtual Environment (PVE) allows a user with limited administrative permissions to hijack the remote console session of a different virtual machine. This occurs when two users attempt to access consoles at the same time, potentially allowing an attacker to view or control a server they are not authorized to access. This could lead to the exposure of sensitive data or unauthorized changes to critical business systems.

Vendors: [Proxmox](https://junglewise.ai/threats/vendors/proxmox).

## Quick answers

**Is CVE-2026-51082 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-51082 being exploited in the wild.

**How severe is CVE-2026-51082?** Informational severity, published 17 July 2026.

**Which products and versions are affected?** Proxmox PVE Container 6.1.x before 6.1.3, 5.3.x before 5.3.4; Proxmox PVE Manager 9.1.x before 9.1.9, 8.4.x before 8.4.19; Proxmox QEMU Server 9.1.x before 9.1.7, 8.4.x before 8.4.7.

**Is there a fix for CVE-2026-51082?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-51082 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-51082?** Check whether you run Proxmox PVE Container, Proxmox PVE Manager or Proxmox QEMU Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A race condition exists between the 'vncproxy' and 'vncwebsocket' API calls in multiple Proxmox VE components, including pve-manager, qemu-server, and pve-container. An attacker who possesses the privileges required to initiate a 'vncproxy' call can exploit this timing window to intercept and hijack a VNC session being established simultaneously by a different legitimate user for a different VM or container. This allows for unauthorized access to the guest console. The issue is resolved in pve-manager 9.1.9/8.4.19, qemu-server 9.1.7/8.4.7, and pve-container 6.1.3/5.3.4.

## Affected products

- Proxmox pve-manager 9.1.x before 9.1.9, 8.4.x before 8.4.19
- Proxmox qemu-server 9.1.x before 9.1.7, 8.4.x before 8.4.7
- Proxmox pve-container 6.1.x before 6.1.3, 5.3.x before 5.3.4

## Timeline

- 2026-07-17: disclosed
- 2026-07-17: advisory

## References

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

## Related threats

- [Proxmox PVE incorrect access control in qemu-server cloudinit/dump API](https://junglewise.ai/threats/cve-2026-51083-proxmox-pve-incorrect-access-control-in-qemu-server-cloudinit)