AndroidOperating system · Google

CVE-2021-25416

MEDIUM · 6.5 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 →
67/100
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
Assuming EL1 is compromised, an improper address validation in RKP prior to SMR JUN-2021 Release 1 allows local attackers to create executable kernel page outside code area.

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

This is a Samsung-specific vulnerability in RKP (Real-time Kernel Protection), their kernel hardening solution. When EL1 (kernel mode) is already compromised, improper address validation allows attackers to create executable kernel pages outside the legitimate code area, potentially enabling code injection or persistence after initial kernel compromise.

MitigationUpdate to Samsung SMR (Security Maintenance Release) June 2021 or later, which contains the patched RKP with proper address validation. For out-of-support devices, consider kernel firmware updates if available.

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
Changed
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N

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 device manufacturer
    Check if the device is a Samsung device (e.g., via 'getprop ro.product.brand' or 'getprop ro.manufacturer').
    Affected if Device is not Samsung - RKP (Real-time Kernel Protection) is Samsung-specific and this CVE does not apply to non-Samsung devices.
  2. Check Android version
    Run 'getprop ro.build.version.release' to determine the installed Android version.
    Affected if Android version is 10.0 or 11.0 - these are the versions affected by this CVE according to the provided product version ranges.
  3. Confirm RKP is present
    Check for RKP presence in the kernel - look for 'rkp' in /proc/cmdline or check /sys/kernel/security/rkp directory existence if available, or use 'getprop ro.boot.rkp' to query RKP status.
    Affected if RKP is not present on the device - this is a Samsung RKP-specific vulnerability and requires RKP to be installed for the flaw to be exploitable.
  4. Verify kernel hardening status
    If RKP is present, check its active protection status via available Samsung-specific security interfaces or sysfs entries related to RKP (e.g., /sys/kernel/security/rkp/rkp_status).
    Affected if RKP is present but disabled or not running - the vulnerability requires RKP to be active; however, note this CVE describes a bypass that applies even when RKP is running.

A Samsung device running Android 10.0 or 11.0 with RKP (Real-time Kernel Protection) enabled is potentially affected by this vulnerability, which allows code injection after initial kernel compromise.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update to Samsung SMR (Security Maintenance Release) June 2021 or later, which contains the patched RKP with proper address validation. For out-of-support devices, consider kernel firmware updates if available.

Fix this in Android Scoped from the published advisory
  • Consultation3.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
24.0 hours of engineering $4,200
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-25416 — 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-2021-25416 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