AndroidOperating system · Google

CVE-2021-0899

MEDIUM · 6.7 CVSS v3.1 Published 2021-12-17
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 apusys, there is a possible memory corruption due to a use after free. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS05672107; Issue ID: ALPS05672059.

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

In apusys (MediaTek's AI Processing Unit driver), a use-after-free vulnerability exists where memory is accessed after being freed, leading to memory corruption. This can be exploited locally to escalate privileges, though System-level access is required to interact with the apusys driver. No user interaction is required for exploitation.

MitigationApply vendor patch ALPS05672107 from MediaTek to address the use-after-free in the apusys driver. This is a firmware/driver-level fix that must be delivered through MediaTek's regular Android update channels.

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= 12.0

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. Confirm MediaTek chipset in use
    Check /proc/cpuinfo or use 'getprop ro.hardware' to identify the SoC vendor. This vulnerability affects only MediaTek-based devices.
    Affected if Device does not use a MediaTek chipset - the apusys driver is MediaTek-specific.
  2. Verify Android version matches affected releases
    Run 'getprop ro.build.version.release' to check if Android version is 10, 11, or 12.
    Affected if Android version is 10, 11, or 12 - these are the affected versions per the CVE.
  3. Check if apusys driver is present
    List /dev or /sys/class for apusys-related device nodes, or check 'lsmod' for apusys-related kernel modules.
    Affected if The apusys driver is loaded and accessible - exploitation requires interaction with this driver.
  4. Check kernel patch level
    Run 'getprop ro.build.version.security_patch' to see the last security patch date applied.
    Affected if Security patch level is before the fix date - the patch ALPS05672107 addresses this issue.

A user is affected if their MediaTek Android device runs version 10, 11, or 12, has the apusys driver loaded, and is missing the vendor-specific patch ALPS05672107.

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 vendor patch ALPS05672107 from MediaTek to address the use-after-free in the apusys driver. This is a firmware/driver-level fix that must be delivered through MediaTek's regular Android update channels.

Fix this in Android Scoped from the published advisory
  • Consultation2.0 h
2.0 hours of engineering $750
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-0899 — 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-2021-0899 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