CVE-2022-20158

Local privilege escalation via backing-device use-after-free

Published Aug 11, 2022 · Updated Dec 17, 2025

Use-after-free in Android kernel backing-device handling allows local users with System privileges to escalate privileges without interaction. After blk_cleanup_queue releases the final backing_dev_info reference, del_gendisk calls bdi_unregister, which dereferences the freed object. Exploitation requires existing System-level execution; the same invalid dereference can corrupt memory or panic the kernel.

CVSS severity6.7
Medium
EPSS probability0.12%
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 kernel backing-device handling allows local users with System privileges to escalate privileges without interaction. After blk_cleanup_queue releases the final backing_dev_info reference, del_gendisk calls bdi_unregister, which dereferences the freed object. Exploitation requires existing System-level execution; the same invalid dereference can corrupt memory or panic the kernel.

The record

CVE
CVE-2022-20158
Published
Aug 11, 2022
Updated
Dec 17, 2025
Vendor
Google Cloud
Product
Android
Classifications
CWE-416, T1404
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 11, 2022CVE publishedPublication date reported by the CVE source.
  2. Dec 17, 2025Record 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 kernel

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Google Cloud · Androidversion=Android kernel

Published CVSS scores

6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.7CISA-ADPCVSS:3.1/AV:L/AC:L/PR:H/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1404Exploitation 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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