AndroidOperating system · Google

CVE-2021-25460

MEDIUM · 5.5 CVSS v3.1 Published 2021-09-09
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
An improper access control vulnerability in sspExit() in BlockchainTZService prior to SMR Sep-2021 Release 1 allows attackers to terminate BlockchainTZService.

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 improper access control vulnerability exists in the sspExit() function within BlockchainTZService. The function can be invoked by unauthorized attackers, allowing them to terminate the BlockchainTZService, resulting in a denial of service condition. This is due to missing or insufficient authorization checks before executing the service termination logic.

MitigationUpdate BlockchainTZService to SMR Sep-2021 Release 1 or later, which includes proper access control enforcement on the sspExit() function to prevent unauthorized service termination.

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
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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. Identify Android version
    Check the device settings or run 'getprop ro.build.version.release' to confirm the Android OS version
    Affected if The version is 10.0 or 11.0 specifically, as these are the affected versions listed
  2. Verify BlockchainTZService presence
    Check if the BlockchainTZService is installed or running on the device using package manager queries or service listing commands
    Affected if BlockchainTZService is present and running on the device
  3. Check SMR update level
    Determine the Samsung Monthly Security Release (SMR) version installed by checking system build properties or security patch date
    Affected if The device has not received the Sep-2021 SMR Release 1 or later update containing the access control fix

A device is affected if it runs Android 10.0 or 11.0, has BlockchainTZService present, and is missing the Sep-2021 SMR security update that adds proper authorization checks to the sspExit() function.

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

Update BlockchainTZService to SMR Sep-2021 Release 1 or later, which includes proper access control enforcement on the sspExit() function to prevent unauthorized service termination.

Recommended fix High confidence

SMR Sep-2021 Release 1

  1. Check for system software updates on the Samsung Android device
  2. Navigate to Settings > Software update > Download and install
  3. Select the Samsung Security Maintenance Release (SMR) for September 2021 or later
  4. Ensure the device restarts to complete the update installation

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

Fix this in Android Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-25460 — 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-2021-25460 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