Proxmox Virtual Environment up to 9.1.8 VNC Proxy/VNC Websocket API race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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2.6$0-$5k1.51

Summaryinfo

A vulnerability was found in Proxmox Virtual Environment up to 9.1.8 and classified as problematic. Impacted is an unknown function of the component VNC Proxy/VNC Websocket API. The manipulation results in race condition. This vulnerability is cataloged as CVE-2026-51082. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Proxmox Virtual Environment up to 9.1.8. It has been classified as problematic. Affected is an unknown code of the component VNC Proxy/VNC Websocket API. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on confidentiality. CVE summarizes:

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.

The advisory is shared for download at forum.proxmox.com. This vulnerability is traded as CVE-2026-51082 since 06/07/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are needed for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 9.1.9 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.7
VulDB Meta Temp Score: 2.6

VulDB Base Score: 2.7
VulDB Temp Score: 2.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Virtual Environment 9.1.9

Timelineinfo

06/07/2026 CVE reserved
07/17/2026 +40 days Advisory disclosed
07/17/2026 +0 days VulDB entry created
07/17/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: forum.proxmox.com
Status: Confirmed

CVE: CVE-2026-51082 (🔒)
GCVE (CVE): GCVE-0-2026-51082
GCVE (VulDB): GCVE-100-379824

Entryinfo

Created: 07/17/2026 17:08
Changes: 07/17/2026 17:08 (53)
Complete: 🔍
Cache ID: 216::103

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