CVE-2021-39684

Local privilege escalation via RWX memory allocation

Published Jan 14, 2022 · Updated Aug 4, 2024

Elevation of privilege in Google Pixel Bootloader Android kernel allows local users to gain higher privileges via RWX memory allocation. The gs101 ABL target_init function in target/slider/target.c can allocate memory with read, write, and execute permissions because of a logic error. Exploitation requires a local low-privilege process on a Pixel device and no user interaction, potentially compromising confidentiality, integrity, and availability.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Elevation of privilege in Google Pixel Bootloader Android kernel allows local users to gain higher privileges via RWX memory allocation. The gs101 ABL target_init function in target/slider/target.c can allocate memory with read, write, and execute permissions because of a logic error. Exploitation requires a local low-privilege process on a Pixel device and no user interaction, potentially compromising confidentiality, integrity, and availability.

The record

CVE
CVE-2021-39684
Published
Jan 14, 2022
Updated
Aug 4, 2024
Vendor
Google
Product
Pixel Bootloader
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 14, 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?

Google · Pixel Bootloaderversion=Android kernel

Published CVSS scores

7.8NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

T1068Exploitation for Privilege Escalation

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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