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    <title>Hardware Security Best Practices</title>
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  <p id="hardware-security">This page contains recommendations to ensure
    that the hardware present on Android devices contributes to raising the
    overall security of the device instead of compromising the security of
    the device.</p>

<h2 id="device-memory">Device memory</h2>

<p>It is important to understand the potential security tradeoffs when
  selecting memory for Android devices. For example, certain types of memory
  may enable the execution of
  <a href="https://en.wikipedia.org/wiki/Row_hammer"
     class="external">Rowhammer</a> style attacks.</p>

<ul>
  <li>Android devices should use memory that contains mitigations against
    Rowhammer style attacks. Device manufacturers should work closely with
    their memory manufacturers for additional details.</li>
</ul>

<h2 id="strongbox-keymaster">StrongBox Keymaster</h2>

<p>It is important to securely store and handle cryptographic keys that are
  available on the device. This is typically done on Android devices by
  utilizing a hardware-backed Keymaster implemented in an isolated environment,
  such as the Trusted Execution Environment (TEE). It is further recommended to
  also support a
  <a href="https://developer.android.com/preview/features/security#hardware-security-module"
     class="external">StrongBox Keymaster</a>, which is implemented in
  tamper-resistant hardware.</p>

<ul>
  <li>Ensure that the StrongBox Keymaster is running in an environment that
    has a discrete CPU, secure storage, a high quality true random number
    generator, tamper resistant packaging, and side channel resistance to meet
    the requirements to qualify as a StrongBox Keymaster. See the Android 9
    CDD, section 9.11.2 for more information on the requirements.</li>
</ul>
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