dbcve.org
AndroidOperating system · Google

CVE-2018-21051

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.x) (Exynos chipsets) software. There is an invalid free in the fingerprint Trustlet, leading to arbitrary code execution. The Samsung ID is SVE-2018-12853 (October 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 memory corruption vulnerability exists in the fingerprint Trustlet (trusted application) on Samsung mobile devices running Android N (7.x) and O (8.x) on Exynos chipsets. The issue is an invalid free (use-after-free condition) in the fingerprint authentication subsystem, which can be exploited to achieve arbitrary code execution with elevated (Trustlet) privileges.

MitigationApply the Samsung security update (SVE-2018-12853) released October 2018 or later, which patches the vulnerable fingerprint Trustlet. Devices should be updated to the latest Samsung security patch level.

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= 8.1

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. Confirm device is a Samsung mobile phone
    Check the device manufacturer through Settings > About Phone or by running 'getprop ro.product.manufacturer' or 'getprop ro.product.brand' in ADB shell
    Affected if Device is not made by Samsung, the vulnerability does not apply
  2. Verify the device uses an Exynos chipset
    Check the chipset through Settings > About Phone > CPU/Microprocessor or by running 'getprop ro.hardware' or 'cat /proc/cpuinfo' in ADB shell; Exynos variants typically show 'exynos' in the hardware property
    Affected if Device uses a Qualcomm/Snapdragon or other non-Exynos chipset, this specific vulnerability does not apply
  3. Check the Android OS version
    Navigate to Settings > About Phone > Android version or run 'getprop ro.build.version.release' in ADB shell
    Affected if Version is NOT 7.0, 7.1.0, 7.1.1, 7.1.2, 8.0, or 8.1, the device is not in the affected version range
  4. Confirm fingerprint authentication is enrolled or in use
    Check if fingerprint is set up by going to Settings > Lock screen and security > Fingerprint or run 'dumpsys fingerprint' in ADB shell to see fingerprint enrollment status
    Affected if Fingerprint authentication is not enrolled or the fingerprint sensor is not used, the vulnerable Trustlet code path is not triggered
  5. Check Samsung security patch level date
    Navigate to Settings > About Phone > Security patch level or run 'getprop ro.build.version.security_patch' in ADB shell
    Affected if The security patch level is earlier than October 2018, the device is likely still running the vulnerable unpatched fingerprint Trustlet

A Samsung device with an Exynos chipset running Android 7.0-8.1 with fingerprint enrolled and a security patch level before October 2018 is likely affected by this CVE.

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 the Samsung security update (SVE-2018-12853) released October 2018 or later, which patches the vulnerable fingerprint Trustlet. Devices should be updated to the latest Samsung security patch level.

Recommended fix High confidence

October 2018 Samsung Security Patch (SVE-2018-12853) or later monthly security update

  1. Check the current Android security patch level on the Samsung device (Settings > About phone > Security patch level)
  2. Verify if the device has received the October 2018 Samsung security update or later
  3. If not patched, check for system updates in Settings > Software update > Download and install
  4. If no update is available through OTA, contact the device carrier or Samsung support for patch availability
  5. For enterprise-managed devices, deploy the latest Samsung security patch via MDM or firmware management tools
Caveat Devices running Android 7.x/8.x that are no longer supported by Samsung may not receive patches; consider upgrading to a currently supported device

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

Fix this in Android Scoped from the published advisory
  • Consultation8.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,940
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,304.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-21051 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2018-21051 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