dbcve.org
AndroidOperating system · Google

CVE-2023-20756

MEDIUM · 6.7 CVSS v3.1 Published 2023-07-04
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 keyinstall, there is a possible out of bounds write due to an integer overflow. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07510064; Issue ID: ALPS07549928.

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

An integer overflow in the keyinstall component leads to an out-of-bounds write, enabling local privilege escalation from System execution privileges. This is a memory corruption vulnerability in Android's key management subsystem that does not require user interaction for exploitation.

MitigationApply vendor patch ALPS07510064 immediately. Until patched, restrict system-level access and monitor for indicators of compromise targeting the keyinstall 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:= 12.0= 13.0

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
    Go to Settings > About Phone > Android version, or run 'getprop ro.build.version.release' via ADB shell
    Affected if Version is exactly 12.0 or 13.0 (note: '=' indicates exact versions, not ranges)
  2. Identify keyinstall component presence
    Check if the keyinstall or keymaster service is running: 'ps -A | grep -i keyinstall' or 'service list' via ADB shell
    Affected if The keyinstall/keymaster service is present and running on the device
  3. Verify current execution context
    Run 'whoami' or 'id' via ADB shell to determine current privilege level
    Affected if Current user context is System (uid 1000) or higher-privilege root, as the vulnerability requires System-level access as attack starting point
  4. Check for keyinstall-related processes
    List all processes containing 'key' in name: 'ps -A | grep -i key' via ADB shell, look for keyinstall, keymaster, or keystore components
    Affected if Key management subsystem processes are active on the device
  5. Review SELinux domain for keyinstall
    Run 'getenforce' and check SELinux status; for keyinstall specific domain, use 'ps -Z' to list process security contexts if available
    Affected if SELinux is in enforcing mode but the keyinstall process domain has exploitable permissions (this requires deeper forensic analysis)

A device is affected only if it runs Android 12.0 or 13.0 exactly AND has the keyinstall component active with System-level execution context available to an attacker.

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 ALPS07510064 immediately. Until patched, restrict system-level access and monitor for indicators of compromise targeting the keyinstall component.

Recommended fix Moderate confidence

Android Security Patch Level containing ALPS07510064 (contact OEM for specific version)

  1. Contact your device manufacturer (OEM) to verify they have incorporated MediaTek patch ALPS07510064
  2. Apply the latest Android security update available for your device, targeting the security patch level that includes this fix
  3. For MediaTek-based devices, verify the security patch level in Settings > About Phone > Security Patch Level includes the fix for CVE-2023-20756
  4. If your device manufacturer has not released an update containing this patch, consider applying available OEM updates or transitioning to a device with current security support
Caveat Security updates are generally backward-compatible; however, verify with your device OEM that the update is stable for your specific device model

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

Fix this in Android Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
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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-2023-20756 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