AndroidOperating system · Google

CVE-2021-0421

MEDIUM · 5.5 CVSS v3.1 Published 2021-09-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
57/100
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 memory management driver, there is a possible information disclosure due to a missing bounds check. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS05403499; Issue ID: ALPS05381235.

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 missing bounds check in a memory management driver allows local information disclosure without requiring additional privileges or user interaction. An attacker could potentially read kernel memory contents due to the unchecked buffer access.

MitigationApply vendor patch ALPS05403499 to address the missing bounds check in the memory management driver component.

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:= 10.0= 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
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 checks

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

  1. Identify Android version
    Open Settings > About Phone > Android version, or run 'adb shell getprop ro.build.version.release'
    Affected if Version displays as 10.0 or 11.0 exactly
  2. Confirm memory management driver presence
    Check if the device uses a memory management driver component - this is typically present in all Android devices handling heap/page allocation
    Affected if Device has any memory management driver active (standard on all Android devices)
  3. Assess local access exposure
    Determine if untrusted local applications or processes can access the device
    Affected if Device allows installation of third-party apps or has multiple user accounts enabled

Device is affected if running Android 10.0 or 11.0 and has an active memory management driver, as the bounds check vulnerability exists in these specific versions.

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 vendor patch ALPS05403499 to address the missing bounds check in the memory management driver component.

Recommended fix Moderate confidence

Android 10.0 with February 2021 Security Patch or later / Android 11.0 with February 2021 Security Patch or later

  1. Check if your device has Android Security Patch Level from February 2021 or later, which includes the fix for CVE-2021-0421
  2. Contact your device manufacturer (OEM) to confirm they have applied MediaTek patch ALPS05403499 for this vulnerability
  3. If your device manufacturer has not released an update containing this patch, consider applying any available Android security updates
  4. Verify the installed patch level by going to Settings > About Phone > Android version or Security Patch Level
Caveat Ensure OEM driver compatibility after applying manufacturer updates; some older devices may not receive patches

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

Fix this in Android Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing5.0 h
  • Review / QA3.0 h
17.0 hours of engineering $2,970
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-0421 — 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-2021-0421 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