Linux Kernel up to 5.10.12 VSOCK net/vmw_vsock/af_vsock.c race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.10.12 (Operating System). This affects some unknown functionality of the file net/vmw_vsock/af_vsock.c of the component VSOCK Handler. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was released 02/05/2021. It is possible to read the advisory at This vulnerability is uniquely identified as CVE-2021-26708 since 02/05/2021. The exploitability is told to be difficult. It is possible to initiate the attack remotely. A authentication is required for exploitation. Technical details and a public exploit are known.

A public exploit has been developed by Alexander Popov (a13xp0p0v) and been published 4 days after the advisory. It is declared as proof-of-concept. The exploit is shared for download at

Upgrading to version 5.10.13 eliminates this vulnerability. The upgrade is hosted for download at Applying a patch is able to eliminate this problem. The bugfix is ready for download at The best possible mitigation is suggested to be patching the affected component.





CPE 2.3infoedit

CPE 2.2infoedit



VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.7

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.0
NVD Vector: 🔒



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

NVD Base Score: 🔒


Class: Race condition
CWE: CWE-362
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Author: Alexander Popov (a13xp0p0v)
Download: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

Threat: 🔍
Adversaries: 🔍
Geopolitics: 🔍
Economy: 🔍
Predictions: 🔍
Remediation: 🔍


Recommended: Patch
Status: 🔍

0-Day Time: 🔒
Exploit Delay Time: 🔍

Upgrade: Kernel 5.10.13


02/05/2021 Advisory disclosed
02/05/2021 +0 days CVE assigned
02/05/2021 +0 days VulDB entry created
02/09/2021 +3 days Exploit disclosed
04/13/2021 +63 days VulDB last update



Status: Confirmed

CVE: CVE-2021-26708 (🔒)
scip Labs:


Created: 02/05/2021 08:14 PM
Updated: 04/13/2021 11:43 AM
Changes: (1) exploit_developer_name
Complete: 🔍
Committer: misc


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