AndroidOperating system · Google

CVE-2020-0309

MEDIUM · 6.7 CVSS v3.1 Published 2020-09-18
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
69/100
Remediation priority · Elevated
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 the Bluetooth server, there is a possible out of bounds write due to an integer overflow. This could lead to local escalation of privilege with System privileges and a Firmware compromise needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11Android ID: A-147227320

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 · moderate confidence

A vulnerability in the Android Bluetooth server allows an integer overflow to cause an out-of-bounds write, enabling local privilege escalation to System level. Exploitation does not require user interaction but does require a compromised firmware state.

MitigationApply the Android-11 security patch that addresses this vulnerability and ensure Bluetooth firmware is updated to the patched version.

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:= 11.0

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

CVSS:3.1/AV:L/AC:L/PR:H/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 is exactly 11.0
    Go to Settings > About Phone > Android version, or run 'getprop ro.build.version.release' via ADB
    Affected if The device is running Android 11.0 exactly (not 11.0.1, 11.0.2, or later)
  2. Verify Bluetooth is enabled
    Check Settings > Bluetooth > On, or run 'settings get global bluetooth_on' via ADB
    Affected if Bluetooth is turned on - this is required for the vulnerable code path to be reachable
  3. Check Android security patch level
    Go to Settings > About Phone > Security patch level, or run 'getprop ro.build.version.security_patch' via ADB
    Affected if The security patch level is earlier than the November 2020 Android 11 security update (date before 2020-11-01)
  4. Inspect Bluetooth firmware version
    Run 'dumpsys bluetooth_manager' or check Settings > About Phone > Bluetooth firmware version if available, or use 'hciattach' commands via ADB
    Affected if The Bluetooth firmware version is older than the patched firmware released with the November 2020 Android security update

A device is affected if it runs Android 11.0 with Bluetooth enabled and lacks the November 2020 security patch, as the integer overflow in the Bluetooth server requires this specific version and configuration to be exploitable.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the Android-11 security patch that addresses this vulnerability and ensure Bluetooth firmware is updated to the patched version.

Fix this in Android Scoped from the published advisory
  • Consultation6.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,600
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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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-2020-0309 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