AndroidOperating system · Google

CVE-2023-21356

HIGH · 8.8 CVSS v3.1 Published 2023-10-30
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
93/100
Remediation priority · Urgent
No privileges Zero-click

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 · unedited
In Bluetooth, there is a possible out of bounds write due to a missing bounds check. This could lead to remote (proximal/adjacent) code execution with no additional execution privileges needed. User interaction is not needed for exploitation.

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 confidence

CVE-2023-21356 is a high-severity vulnerability in the Android Bluetooth stack where a missing bounds check allows an out-of-bounds write. An attacker within Bluetooth range can exploit this to achieve remote code execution without requiring any user interaction or elevated privileges.

MitigationApply the Android security patch that includes the fix for this vulnerability. Users should ensure their devices receive the latest Bluetooth-related security updates.

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
AndroidOperating system
Affected:= 14.0

CVSS 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
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 checks

Work through these to decide whether this CVE applies to you.

  1. Check Android version
    Go to Settings > About Phone > Android version. Verify the exact version is 14.0.
    Affected if Android version is exactly 14.0
  2. Confirm Bluetooth is enabled
    Go to Settings > Bluetooth and verify Bluetooth is turned ON.
    Affected if Bluetooth is enabled on the device
  3. Check security patch level
    Go to Settings > About Phone > Security patch level. Note the date of the installed security update.
    Affected if Security patch level is earlier than the CVE fix date (April 2024 or earlier)

Device is affected if it runs Android 14.0 with Bluetooth enabled and has a security patch level prior to the fix being applied.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the Android security patch that includes the fix for this vulnerability. Users should ensure their devices receive the latest Bluetooth-related security updates.

Recommended fix High confidence

Android 14.0 with latest security patch (April 2023 security update or later)

  1. 1. Go to Settings on the Android device
  2. 2. Navigate to System > System Update (or Settings > About Phone > Software Update)
  3. 3. Check for updates and download any available updates
  4. 4. Install the latest Android security patch update (April 2023 security patch or later)
  5. 5. Verify the update was installed by checking Settings > About Phone > Android version and Build number
Caveat Users should back up important data before performing system updates as a precaution

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Android Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA6.0 h
42.0 hours of engineering $7,360
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-21356 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-21356 in production — separate from our analysis above.

No notes yet

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What this is

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.

What belongs here
  • 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