CVE-2021-39688

Local information disclosure via out-of-bounds read

Published Feb 11, 2022 · Updated Aug 4, 2024

Out-of-bounds read in the Android kernel's google_battery component allows local users to disclose information without user interaction. The Pixel bulletin identifies google_battery as the affected component, but Google marks the underlying Android bug nonpublic and does not disclose the buffer operation or triggering input. Exploitation requires a local low-privileged context on an affected Pixel device and exposes memory contents without reported integrity or availability impact.

CVSS severity5.5
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

Out-of-bounds read in the Android kernel's google_battery component allows local users to disclose information without user interaction. The Pixel bulletin identifies google_battery as the affected component, but Google marks the underlying Android bug nonpublic and does not disclose the buffer operation or triggering input. Exploitation requires a local low-privileged context on an affected Pixel device and exposes memory contents without reported integrity or availability impact.

The record

CVE
CVE-2021-39688
Published
Feb 11, 2022
Updated
Aug 4, 2024
Vendor
Google Cloud
Product
Android
Classifications
CWE-125
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 11, 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?

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  1. Affected versionversion=Android kernel

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google Cloud · Androidversion=Android kernel

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
2.1NIST NVDAV:L/AC:L/Au:N/C:P/I:N/A:N

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-125Out-of-bounds Read

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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