AndroidOperating system · Google

CVE-2018-21044

CRITICAL · 9.8 CVSS v3.1 Published 2020-04-08
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable 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
An issue was discovered on Samsung mobile devices with N(7.x) and O(8.0) software. The sem Trustlet has a buffer overflow that leads to arbitrary TEE code execution. The Samsung IDs are SVE-2018-13230, SVE-2018-13231, SVE-2018-13232, SVE-2018-13233 (December 2018).

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

A buffer overflow vulnerability exists in the sem Trustlet (a Trusted Execution Environment application) on Samsung mobile devices running Android N (7.x) and O (8.0). This flaw allows an attacker to achieve arbitrary code execution within the TEE, bypassing hardware-backed security boundaries.

MitigationApply Samsung security patches released after December 2018 (SVE-2018-13230 through SVE-2018-13233). Devices that cannot receive firmware updates should be considered at high risk for TEE compromise.

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:= 7.0= 7.1.0= 7.1.1= 7.1.2= 8.0

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

CVSS:3.1/AV:N/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, or run 'getprop ro.build.version.release' via ADB
    Affected if Version is 7.0, 7.1.0, 7.1.1, 7.1.2, or 8.0
  2. Confirm device is Samsung
    Go to Settings > About Phone > Manufacturer, or run 'getprop ro.product.manufacturer' via ADB
    Affected if Manufacturer is Samsung (the sem Trustlet is Samsung-specific)
  3. Verify TEE is present
    Run 'getprop ro.trustonic.teed.status' or check /vendor/bin/teed for existence via ADB shell
    Affected if TEE status returns 'enabled' or /vendor/bin/teed exists (the vulnerability resides in the TEE)
  4. Identify sem Trustlet
    Check for /vendor/firmware/semTrustlet or run 'ls /vendor/firmware/*sem*' via ADB shell
    Affected if The sem Trustlet binary is present on the device

User is affected if running Android 7.0-8.0 on a Samsung device with an active TEE containing the sem Trustlet component.

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 Samsung security patches released after December 2018 (SVE-2018-13230 through SVE-2018-13233). Devices that cannot receive firmware updates should be considered at high risk for TEE compromise.

Recommended fix High confidence

December 2018 security patch level or later for affected Samsung devices (Android N 7.x and O 8.0)

  1. 1. Navigate to Settings on the Samsung device
  2. 2. Select 'About phone' or 'About device'
  3. 3. Tap on 'Software update' or 'System updates'
  4. 4. Check for and install any available updates
  5. 5. Ensure the device receives the December 2018 security patch level or later (SVE-2018-13230, SVE-2018-13231, SVE-2018-13232, SVE-2018-13233)
Caveat Older devices may no longer receive security updates; consider upgrading to a newer device model if the update is unavailable

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

Fix this in Android Scoped from the published advisory
  • Consultation4.0 h
  • Testing8.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,360
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,776.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-21044 — 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-2018-21044 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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