CVE-2021-0535

Local privilege escalation via queued interface callback

Published Jun 22, 2021 · Updated Aug 3, 2024

Use-after-free in Android 11's Wi-Fi control interface allows local users with System privileges to escalate privileges without interaction. If driver initialization fails after a control message is queued, conditional interface deinitialization leaves an eloop timeout holding a freed wpa_s pointer. Triggering the stale wpas_ctrl_msg_queue_timeout callback requires existing local System execution privileges and can yield higher local privileges.

CVSS severity6.7
Medium
EPSS probability0.11%
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 Android 11's Wi-Fi control interface allows local users with System privileges to escalate privileges without interaction. If driver initialization fails after a control message is queued, conditional interface deinitialization leaves an eloop timeout holding a freed wpa_s pointer. Triggering the stale wpas_ctrl_msg_queue_timeout callback requires existing local System execution privileges and can yield higher local privileges.

The record

CVE
CVE-2021-0535
Published
Jun 22, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Android
Classifications
CWE-416, T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jun 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

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  1. Affected versionversion=Android-11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Google Cloud · Androidversion=Android-11

Published CVSS scores

6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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