AndroidOperating system · Google

CVE-2015-6640

HIGH · 7.8 CVSS v3.0 Published 2016-01-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
81/100
Remediation priority · High
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
The prctl_set_vma_anon_name function in kernel/sys.c in Android before 5.1.1 LMY49F and 6.0 before 2016-01-01 does not ensure that only one vma is accessed in a certain update action, which allows attackers to gain privileges or cause a denial of service (vma list corruption) via a crafted application, aka internal bug 20017123.

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 race condition exists in the prctl_set_vma_anon_name function in the Android kernel (kernel/sys.c) where the function fails to ensure only one VMA (virtual memory area) is accessed during certain update operations. This allows an attacker to trigger vma list corruption through a crafted application, potentially achieving privilege escalation or causing a denial of service.

MitigationApply the Android security updates for LMY49F (5.1.1) or the January 2016 update for Android 6.0, which contain the kernel patch addressing the race condition in prctl_set_vma_anon_name.

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:= 4.4.4= 5.0= 5.1.1= 6.0

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

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/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. Check Android OS version
    Go to Settings > About Phone > Android version, or run 'getprop ro.build.version.release' via ADB shell
    Affected if Version is 4.4.4, 5.0, 5.1.1, or 6.0 (these are the affected versions)
  2. Check kernel version
    Run 'cat /proc/version' via ADB shell or check Kernel version in Settings > About Phone > Kernel version
    Affected if Kernel is older than the January 2016 Android 6.0 security patch or LMY49F (5.1.1) patch level
  3. Verify security patch level
    Run 'getprop ro.build.version.security_patch' via ADB shell
    Affected if The patch level is empty, earlier than 2016-01-01 for Android 6.0, or earlier than LMY49F for Android 5.1.1
  4. Confirm vulnerable kernel function exists
    Check if /proc/kallsyms contains 'prctl_set_vma_anon_name' by running 'cat /proc/kallsyms | grep prctl_set_vma_anon_name' via ADB shell
    Affected if The function symbol exists in the kernel (indicates the vulnerable code path is present)

The device is affected if it runs Android 4.4.4, 5.0, 5.1.1, or 6.0 and has a kernel version or security patch level predating the January 2016 Android update (for 6.0) or LMY49F (for 5.1.1).

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

Apply the Android security updates for LMY49F (5.1.1) or the January 2016 update for Android 6.0, which contain the kernel patch addressing the race condition in prctl_set_vma_anon_name.

Fix this in Android Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2015-6640 — 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-2015-6640 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