CVE-2021-47583

Undefined locking behavior via premature mutex use

Published Jun 19, 2024 · Updated May 11, 2026

Use of an uninitialized mutex in the Linux mxl111sf driver allows local users to reach undefined kernel behavior during frontend attachment. mxl111sf_ctrl_msg locks state->msg_lock before the later init callback initializes it because frontend attachment runs first. Reachability requires mxl111sf frontend initialization, and published sources establish no data access, code execution, or specific crash consequence.

CVSS severityUnavailable
Unscored
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

Use of an uninitialized mutex in the Linux mxl111sf driver allows local users to reach undefined kernel behavior during frontend attachment. mxl111sf_ctrl_msg locks state->msg_lock before the later init callback initializes it because frontend attachment runs first. Reachability requires mxl111sf frontend initialization, and published sources establish no data access, code execution, or specific crash consequence.

The record

CVE
CVE-2021-47583
Published
Jun 19, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-908
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jun 19, 2024CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record 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=3.7
  2. Affected versionversion=8572211842afc53c8450fb470f2b8d02ba7592e0 <44870a9e7a3c24acbb3f888b2a7cc22c9bdf7e7f
  3. Affected versionversion=8572211842afc53c8450fb470f2b8d02ba7592e0 <4b2d9600b31f9ba7adbc9f3c54a068615d27b390
  4. Affected versionversion=8572211842afc53c8450fb470f2b8d02ba7592e0 <8c6fdf62bfe1bc72bfceeaf832ef7499c7ed09ba
  5. Affected versionversion=8572211842afc53c8450fb470f2b8d02ba7592e0 <96f182c9f48b984447741f054ec301fdc8517035
  6. Affected versionversion=8572211842afc53c8450fb470f2b8d02ba7592e0 <b99bdf127af91d53919e96292c05f737c45ea59a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=3.7; version=8572211842afc53c8450fb470f2b8d02ba7592e0 <44870a9e7a3c24acbb3f888b2a7cc22c9bdf7e7f; version=8572211842afc53c8450fb470f2b8d02ba7592e0 <4b2d9600b31f9ba7adbc9f3c54a068615d27b390; version=8572211842afc53c8450fb470f2b8d02ba7592e0 <8c6fdf62bfe1bc72bfceeaf832ef7499c7ed09ba; version=8572211842afc53c8450fb470f2b8d02ba7592e0 <96f182c9f48b984447741f054ec301fdc8517035; version=8572211842afc53c8450fb470f2b8d02ba7592e0 <b99bdf127af91d53919e96292c05f737c45ea59a

Published CVSS scores

No CVSS assessment is available in this record.

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
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-908Use of Uninitialized Resource

Public exploit references

No public exploit references are available in this record.

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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