CVE-2021-47525

Local use-after-free via underegistered LiteUART port

Published May 24, 2024 · Updated May 11, 2026

Use-after-free in the Linux LiteUART serial driver from 5.11 through 5.15.6 allows local users to access a port after driver unbinding. liteuart_remove() erases the device from its tracking array without first calling uart_remove_one_port(), leaving serial core resources registered after the driver data is released. Exploitation requires local access and the ability to unbind a bound LiteUART device; published sources establish stale access and a memory leak but no demonstrated code execution.

CVSS severity7.8
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Linux LiteUART serial driver from 5.11 through 5.15.6 allows local users to access a port after driver unbinding. liteuart_remove() erases the device from its tracking array without first calling uart_remove_one_port(), leaving serial core resources registered after the driver data is released. Exploitation requires local access and the ability to unbind a bound LiteUART device; published sources establish stale access and a memory leak but no demonstrated code execution.

The record

CVE
CVE-2021-47525
Published
May 24, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 24, 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=1da81e5562fac8286567422cc56a7fbd0dc646d4 <05f929b395dec8957b636ff14e66b277ed022ed9
  2. Affected versionversion=1da81e5562fac8286567422cc56a7fbd0dc646d4 <602824cf9aa9db8830ffe5cfb2cd54365cada4fe
  3. Affected versionversion=5.11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da81e5562fac8286567422cc56a7fbd0dc646d4 <05f929b395dec8957b636ff14e66b277ed022ed9; version=1da81e5562fac8286567422cc56a7fbd0dc646d4 <602824cf9aa9db8830ffe5cfb2cd54365cada4fe; version=5.11

Published CVSS scores

7.8NVDCVSS:3.1/AV:L/AC:L/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free

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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