CVE-2021-39787

Local privilege escalation via arbitrary Activity launch

Published Mar 30, 2022 · Updated Aug 4, 2024

Confused-deputy behavior in Google Cloud Android 12L SystemUI allows local users to gain elevated privileges through an arbitrary Activity launch. SystemUI launches an arbitrary Activity as a confused deputy, but the affected function and validation failure have not been publicly disclosed. Exploitation requires local access and user interaction; no additional execution privileges are needed, and successful exploitation elevates privilege.

CVSS severity7.8
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Confused-deputy behavior in Google Cloud Android 12L SystemUI allows local users to gain elevated privileges through an arbitrary Activity launch. SystemUI launches an arbitrary Activity as a confused deputy, but the affected function and validation failure have not been publicly disclosed. Exploitation requires local access and user interaction; no additional execution privileges are needed, and successful exploitation elevates privilege.

The record

CVE
CVE-2021-39787
Published
Mar 30, 2022
Updated
Aug 4, 2024
Vendor
Google Cloud
Product
Android
Classifications
CWE-610, T1404
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 30, 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-12L

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Google Cloud · Androidversion=Android-12L

Published CVSS scores

9.3NIST NVDAV:N/AC:M/Au:N/C:C/I:C/A:C
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-610Externally Controlled Reference to a Resource in Another Sphere
T1404Exploitation 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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