CVE-2021-39745
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn DevicePolicyManager, there is a possible way to determine whether an app is installed, without query permissions, due to side channel information disclosure. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-12LAndroid ID: A-206127671
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceIn DevicePolicyManager on Android-12L, a side-channel information disclosure allows local apps to determine whether another app is installed without the required query permissions. This privacy bypass requires no additional privileges or user interaction to exploit.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 12.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check Android version numberNavigate to Settings > About Phone > Android version, or run 'getprop ro.build.version.release' via ADB shellAffected if Version displays as 12.1 or Android-12L specifically
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Verify Android 12L build IDNavigate to Settings > About Phone > Build number, or run 'getprop ro.build.id' via ADB shellAffected if Build ID matches the Android-12L series (such as S2B2, S2B3)
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Confirm security patch levelNavigate to Settings > About Phone > Security patch level, or run 'getprop ro.build.version.security_patch' via ADB shellAffected if Security patch level is earlier than January 2022 or cannot be determined
The device is affected if it runs Android 12.1 (Android-12L) and has not received the January 2022 or later security update, as the vulnerability resides in the DevicePolicyManager component's handling of app query requests.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedApply the Google security patch for Android-12L (January 2022 security update or later) which addresses this vulnerability in the DevicePolicyManager component.
Latest Android security patch level (typically Android 12L receives monthly security updates; the fix is included in subsequent security bulletin releases after the vulnerability was disclosed)
- Check the current Android version and security patch level on the device in Settings > About Phone > Android version and Build number
- Ensure the device receives the latest Android security update by checking for system updates in Settings > System > Security Update
- Apply any available system updates that include the Android security bulletin for the month containing the fix for A-206127671
- Verify the security patch level has been updated to include the fix for this vulnerability
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-39745 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-39745 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data