CVE-2021-39666

Local information disclosure via unterminated metrics string

Published Feb 11, 2022 · Updated Aug 4, 2024

Out-of-bounds read in Android 11 and 12 Media Framework allows local users to disclose process memory through a malformed metrics buffer. MediaMetricsItem.h's string extract routine constructed a string from the current buffer pointer without first finding a null terminator within the supplied buffer limit. A local malicious application needs no additional execution privileges or user interaction, and the bounded impact is information disclosure.

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 Android 11 and 12 Media Framework allows local users to disclose process memory through a malformed metrics buffer. MediaMetricsItem.h's string extract routine constructed a string from the current buffer pointer without first finding a null terminator within the supplied buffer limit. A local malicious application needs no additional execution privileges or user interaction, and the bounded impact is information disclosure.

The record

CVE
CVE-2021-39666
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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Android-11 Android-12

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google Cloud · Androidversion=Android-11 Android-12

Published CVSS scores

2.1NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:P/I:N/A:N
5.5NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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.

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Technologies

Your stack

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Your stack

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