CVE-2021-39713Public exploit

Local code execution via scheduler race

Published Mar 16, 2022 · Updated Aug 4, 2024

A race condition in Linux Kernel Android kernel allows local users to execute arbitrary code via crafted scheduling operations. The network scheduling subsystem can free a shared object while another execution path still uses it, creating a use-after-free race. Low-privilege local access is required; exploitation can crash the system or run code with kernel privileges.

CVSS severity7.0
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A race condition in Linux Kernel Android kernel allows local users to execute arbitrary code via crafted scheduling operations. The network scheduling subsystem can free a shared object while another execution path still uses it, creating a use-after-free race. Low-privilege local access is required; exploitation can crash the system or run code with kernel privileges.

The record

CVE
CVE-2021-39713
Published
Mar 16, 2022
Updated
Aug 4, 2024
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-362, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 16, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Android kernel

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=Android kernel

Published CVSS scores

6.9NVDAV:L/AC:M/Au:N/C:C/I:C/A:C
7.0NVDCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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