AndroidOperating system · Google

CVE-2015-9021

MEDIUM · 5.5 CVSS v3.0 Published 2017-06-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
58/100
Remediation priority · Elevated
No privileges

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
In all Android releases from CAF using the Linux kernel, access control to SMEM memory was not enabled.

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 vulnerability in Android CAF Linux kernels lacked access control enforcement for SMEM (Shared Memory) regions, allowing unauthorized processes to potentially read or write to shared memory that should be protected.

MitigationEnable and configure proper access control mechanisms for SMEM memory regions in the Linux kernel, typically requiring kernel-level changes and security module configuration.

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:all versions

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
None
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/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 the kernel type and version
    Check /proc/version or 'un -a' output for 'CAF' (Code Aurora Forum) or 'Linux' kernel strings, and note the exact version number
    Affected if The kernel is a CAF build and the version falls within the affected range (or if version cannot be determined but CAF kernel is confirmed)
  2. Determine if SMEM is in use
    Check for SMEM-related kernel config options in /boot/config-* or via 'grep -i smem /proc/config.gz' if available, or look for smem entries in /proc/meminfo
    Affected if SMEM (Shared Memory) is enabled and accessible on the system
  3. Verify SMEM access control configuration
    Examine /sys/module/smem*/parameters/* or check for smem access control files in /proc/smem/ and verify if proper ACLs or security modules are restricting access
    Affected if SMEM regions can be accessed without proper access control restrictions or the access control configuration is missing or misconfigured
  4. Check for unauthorized SMEM access capability
    Attempt to read SMEM region files if accessible (e.g., in /proc/smem/) or check system logs for any smem-related access attempts
    Affected if Non-privileged processes can read or write to SMEM regions without proper authorization checks

The environment is affected if running a CAF-based Android Linux kernel with SMEM enabled and lacking proper access control enforcement for SMEM regions.

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

Enable and configure proper access control mechanisms for SMEM memory regions in the Linux kernel, typically requiring kernel-level changes and security module configuration.

Fix this in Android Scoped from the published advisory
  • Consultation8.0 h
  • Implementation24.0 h
  • Testing16.0 h
  • Review / QA8.0 h
56.0 hours of engineering $9,760
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2015-9021 — 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-2015-9021 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