CVE-2021-39644

Elevation of privilege

Published Dec 15, 2021 · Updated Aug 4, 2024

Elevation of privilege in the Google Pixel bootloader allows attackers to gain elevated privileges through an undisclosed vector. Google identifies the component and impact but has not published the vulnerable code path or the operation it performs on untrusted input. The required access level, affected Pixel models, and resulting privilege boundary are not publicly specified, so affected state cannot be distinguished from fixed state using the available record.

CVSS severity9.8
Critical
EPSS probability0.45%
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 the Google Pixel bootloader allows attackers to gain elevated privileges through an undisclosed vector. Google identifies the component and impact but has not published the vulnerable code path or the operation it performs on untrusted input. The required access level, affected Pixel models, and resulting privilege boundary are not publicly specified, so affected state cannot be distinguished from fixed state using the available record.

The record

CVE
CVE-2021-39644
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Google
Product
Pixel Bootloader
Classifications
T1068
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Dec 15, 2021CVE 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 vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Google · Pixel Bootloaderversion=Android kernel

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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)
VectorUnavailable
PrivilegesUnavailable
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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