dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 20 Jul 2023.
AndroidOperating system · Samsung

CVE-2021-25394

MEDIUM · 6.4 CVSS v3.1 Published 2021-06-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
96/100
Remediation priority · Urgent
In the wild 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
A use after free vulnerability via race condition in MFC charger driver prior to SMR MAY-2021 Release 1 allows arbitrary write given a radio privilege is compromised.

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

A use-after-free vulnerability exists in the MFC charger driver due to a race condition. An attacker who has compromised radio privilege can exploit this race condition to achieve arbitrary write primitive, potentially leading to privilege escalation or system compromise.

MitigationUpdate the device firmware to SMR MAY-2021 Release 1 or later, which contains the patched MFC charger driver addressing the race condition and use-after-free vulnerability.

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:= 8.1= 9.0= 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
High
Privileges
High
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:H/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. Identify the device manufacturer and model
    Check the device settings or use 'getprop ro.product.manufacturer' and 'getprop ro.product.model' to confirm this is a Samsung device
    Affected if The device is not made by Samsung - the vulnerability only affects Samsung Android devices
  2. Determine the Android version
    Use 'getprop ro.build.version.release' or check Settings > About Phone > Android version
    Affected if The Android version is 8.1, 9.0, 10.0, or 11.0 - these are the versions listed as affected
  3. Check the SMR (Samsung Maintenance Release) version
    Use 'getprop ro.build.version.sem' or check Settings > About Phone > Software info > Baseband version - SMR versions follow format like SMR-xx-RELEASE-x
    Affected if The SMR version is earlier than MAY-2021 Release 1 (e.g., SMR-APR-2021-RELEASE-1 or earlier) or cannot be determined, indicating the patch may not be applied
  4. Verify the MFC charger driver presence
    Check for the MFC charger kernel module by examining '/sys/module/' directory or using 'lsmod' command if available, looking for modules related to 'mfc_charger' or 'sec_mfc'
    Affected if The MFC charger driver module is loaded or present on the device - the vulnerability exists in this specific driver

A user is affected if they have a Samsung Android device running version 8.1, 9.0, 10.0, or 11.0 with an SMR version earlier than MAY-2021 Release 1, and the MFC charger driver is present on the system.

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 the device firmware to SMR MAY-2021 Release 1 or later, which contains the patched MFC charger driver addressing the race condition and use-after-free vulnerability.

Recommended fix Moderate confidence

SMR MAY-2021 Release 1 (May 2021 Security Patch Level)

  1. Check your Samsung device's current Android security patch level in Settings > About Phone > Software Information
  2. Ensure your device received the May 2021 security update (SMR MAY-2021 Release 1)
  3. Go to Settings > Software Update and download/install any available updates
  4. Verify the security patch level shows May 2021 or later after updating
Caveat Samsung monthly security updates typically do not introduce breaking changes; they are cumulative and include previous months' patches

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

Fix this in Android Exploited in the wild — priority engagement
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,888.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-25394 — 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-2021-25394 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