CVE-2021-39700

Local network data disclosure via adbd policy error

Published May 10, 2022 · Updated Aug 4, 2024

Information disclosure in Android 10 through 12 allows local users to read network connection data via an adbd SELinux policy error. The adbd.te policy omitted read permissions for /proc/net/tcp, tcp6, udp, and udp6, causing the CTS Listening Ports Test to return invalid results and exposing connection data. Local access is required, no additional execution privilege or user interaction is needed, and the reported consequence is information disclosure without 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

Information disclosure in Android 10 through 12 allows local users to read network connection data via an adbd SELinux policy error. The adbd.te policy omitted read permissions for /proc/net/tcp, tcp6, udp, and udp6, causing the CTS Listening Ports Test to return invalid results and exposing connection data. Local access is required, no additional execution privilege or user interaction is needed, and the reported consequence is information disclosure without integrity or availability impact.

The record

CVE
CVE-2021-39700
Published
May 10, 2022
Updated
Aug 4, 2024
Vendor
Google Cloud
Product
Android
Classifications
T1049
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 10, 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-10 Android-11 Android-12

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google Cloud · Androidversion=Android-10 Android-11 Android-12

Published CVSS scores

5.5Google AndroidCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
2.1NVDAV: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

T1049System Network Connections Discovery

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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