CVE-2021-0306

Local privilege escalation via stale permission retention

Published Jan 11, 2021 · Updated Aug 3, 2024

Privilege escalation in Android 8.0, 8.1, 9, 10, and 11 allows local users to gain activity-recognition permission during an OS upgrade. PermissionManagerService.addAllPermissions fails to revoke an existing grant when its owner changes or its protection level becomes runtime. Exploitation requires an installed app and a major-version upgrade, but no user interaction, and leaves the app with the permission without confirmation.

CVSS severity7.8
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Privilege escalation in Android 8.0, 8.1, 9, 10, and 11 allows local users to gain activity-recognition permission during an OS upgrade. PermissionManagerService.addAllPermissions fails to revoke an existing grant when its owner changes or its protection level becomes runtime. Exploitation requires an installed app and a major-version upgrade, but no user interaction, and leaves the app with the permission without confirmation.

The record

CVE
CVE-2021-0306
Published
Jan 11, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Android
Classifications
CWE-269, CAPEC-233, CAPEC-58, CAPEC-122, T1404
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=Android-10
  2. Affected versionversion=Android-11
  3. Affected versionversion=Android-8.0
  4. Affected versionversion=Android-8.1
  5. Affected versionversion=Android-9

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google Cloud · Androidversion=Android-10; version=Android-11; version=Android-8.0; version=Android-8.1; version=Android-9

Published CVSS scores

7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/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 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-269Improper Privilege Management
CAPEC-233Privilege Escalation
CAPEC-58Restful Privilege Elevation
CAPEC-122Privilege Abuse
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo