MINI MINI MANI MO
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<ol class="chapter"><li class="chapter-item expanded "><a href="../../Introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="../../manual/Installing.html"><strong aria-hidden="true">2.</strong> Installing</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/Installing/Packages.html"><strong aria-hidden="true">2.1.</strong> Packages</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Docker.html"><strong aria-hidden="true">2.2.</strong> Docker</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Installing-from-source-Unix.html"><strong aria-hidden="true">2.3.</strong> Unix from source (v0.104+)</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Installing-from-source-Unix-old.html"><strong aria-hidden="true">2.4.</strong> Unix from source (v0.103-)</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Installing-from-source-Windows.html"><strong aria-hidden="true">2.5.</strong> Windows from source</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Community-projects.html"><strong aria-hidden="true">2.6.</strong> Community Projects</a></li><li class="chapter-item expanded "><a href="../../manual/Installing/Add-clamav-user.html"><strong aria-hidden="true">2.7.</strong> Add a service user account</a></li></ol></li><li class="chapter-item expanded "><a href="../../manual/Usage.html"><strong aria-hidden="true">3.</strong> Usage</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/Usage/Configuration.html"><strong aria-hidden="true">3.1.</strong> Configuration</a></li><li class="chapter-item expanded "><a href="../../manual/Usage/SignatureManagement.html"><strong aria-hidden="true">3.2.</strong> Updating Signature Databases</a></li><li class="chapter-item expanded "><a href="../../manual/Usage/Scanning.html"><strong aria-hidden="true">3.3.</strong> Scanning</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/OnAccess.html"><strong aria-hidden="true">3.3.1.</strong> On-Access Scanning</a></li></ol></li><li class="chapter-item expanded "><a href="../../manual/Usage/Services.html"><strong aria-hidden="true">3.4.</strong> Running ClamAV Services</a></li><li class="chapter-item expanded "><a href="../../manual/Usage/ReportABug.html"><strong aria-hidden="true">3.5.</strong> Report a Bug</a></li></ol></li><li class="chapter-item expanded "><a href="../../manual/Signatures.html"><strong aria-hidden="true">4.</strong> Signatures</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/Signatures/DatabaseInfo.html"><strong aria-hidden="true">4.1.</strong> CVD Info File</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/DynamicConfig.html"><strong aria-hidden="true">4.2.</strong> Dynamic Configuration Settings</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/AuthenticodeRules.html"><strong aria-hidden="true">4.3.</strong> Trusted and Revoked EXE Certificates</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/FileTypeMagic.html" class="active"><strong aria-hidden="true">4.4.</strong> File Type Recognition</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/AllowLists.html"><strong aria-hidden="true">4.5.</strong> Allow Lists</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/HashSignatures.html"><strong aria-hidden="true">4.6.</strong> Hash-based Signatures</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/BodySignatureFormat.html"><strong aria-hidden="true">4.7.</strong> Content-based Signature Format</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/Signatures/LogicalSignatures.html"><strong aria-hidden="true">4.7.1.</strong> Logical Signatures</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/ExtendedSignatures.html"><strong aria-hidden="true">4.7.2.</strong> Extended Signatures</a></li></ol></li><li class="chapter-item expanded "><a href="../../manual/Signatures/YaraRules.html"><strong aria-hidden="true">4.8.</strong> YARA Rules</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/PhishSigs.html"><strong aria-hidden="true">4.9.</strong> Phishing Signatures</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/BytecodeSignatures.html"><strong aria-hidden="true">4.10.</strong> Bytecode Signatures</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/ContainerMetadata.html"><strong aria-hidden="true">4.11.</strong> Container Metadata Signatures</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/EncryptedArchives.html"><strong aria-hidden="true">4.12.</strong> Archive Passwords (experimental)</a></li><li class="chapter-item expanded "><a href="../../manual/Signatures/SignatureNames.html"><strong aria-hidden="true">4.13.</strong> Signature Names</a></li></ol></li><li class="chapter-item expanded "><a href="../../manual/Development.html"><strong aria-hidden="true">5.</strong> For Developers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../manual/Development/github-pr-basics.html"><strong aria-hidden="true">5.1.</strong> Pull Request Basics</a></li><li class="chapter-item expanded "><a href="../../manual/Development/clamav-git-work-flow.html"><strong aria-hidden="true">5.2.</strong> ClamAV Git Work Flow</a></li><li class="chapter-item expanded "><a href="../../manual/Development/personal-forks.html"><strong aria-hidden="true">5.3.</strong> Working with Your Fork</a></li><li class="chapter-item expanded "><a href="../../manual/Development/testing-pull-requests.html"><strong aria-hidden="true">5.4.</strong> Reviewing Pull Requests</a></li><li class="chapter-item expanded "><a href="../../manual/Development/development-builds.html"><strong aria-hidden="true">5.5.</strong> Building for Development</a></li><li class="chapter-item expanded "><a href="../../manual/Development/build-installer-packages.html"><strong aria-hidden="true">5.6.</strong> Building the Installer Packages</a></li><li class="chapter-item expanded "><a href="../../manual/Development/tips-and-tricks.html"><strong aria-hidden="true">5.7.</strong> Dev Tips & Tricks</a></li><li class="chapter-item expanded "><a href="../../manual/Development/performance-profiling.html"><strong aria-hidden="true">5.8.</strong> Performance Profiling</a></li><li class="chapter-item expanded "><a href="../../manual/Development/code-coverage.html"><strong aria-hidden="true">5.9.</strong> Computing Code Coverage</a></li><li class="chapter-item expanded "><a href="../../manual/Development/fuzzing-sanitizers.html"><strong aria-hidden="true">5.10.</strong> Fuzzing Sanitizers</a></li><li class="chapter-item expanded "><a href="../../manual/Development/libclamav.html"><strong aria-hidden="true">5.11.</strong> libclamav</a></li><li class="chapter-item expanded "><a href="../../manual/Development/Contribute.html"><strong aria-hidden="true">5.12.</strong> Contribute</a></li></ol></li><li class="chapter-item expanded "><a href="../../faq/faq.html"><strong aria-hidden="true">6.</strong> Frequently Asked Questions</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../faq/faq-whichversion.html"><strong aria-hidden="true">6.1.</strong> Selecting the Right Version of ClamAV for You</a></li><li class="chapter-item expanded "><a href="../../faq/faq-freshclam.html"><strong aria-hidden="true">6.2.</strong> FreshClam (Signature Updater)</a></li><li class="chapter-item expanded "><a href="../../faq/faq-cvd.html"><strong aria-hidden="true">6.3.</strong> Signature Database (CVD)</a></li><li class="chapter-item expanded "><a href="../../faq/faq-misc.html"><strong aria-hidden="true">6.4.</strong> Misc</a></li><li class="chapter-item expanded "><a href="../../faq/faq-ml.html"><strong aria-hidden="true">6.5.</strong> Mailing Lists</a></li><li class="chapter-item expanded "><a href="../../faq/faq-safebrowsing.html"><strong aria-hidden="true">6.6.</strong> Safe Browsing</a></li><li class="chapter-item expanded "><a href="../../faq/faq-troubleshoot.html"><strong aria-hidden="true">6.7.</strong> Troubleshooting</a></li><li class="chapter-item expanded "><a href="../../faq/faq-scan-alerts.html"><strong aria-hidden="true">6.8.</strong> Interpreting Scan Alerts</a></li><li class="chapter-item expanded "><a href="../../faq/faq-upgrade.html"><strong aria-hidden="true">6.9.</strong> Upgrading</a></li><li class="chapter-item expanded "><a href="../../faq/faq-rust.html"><strong aria-hidden="true">6.10.</strong> Rust</a></li><li class="chapter-item expanded "><a href="../../faq/faq-win32.html"><strong aria-hidden="true">6.11.</strong> Win32</a></li><li class="chapter-item expanded "><a href="../../faq/faq-pua.html"><strong aria-hidden="true">6.12.</strong> PUA (Potentially Unwanted Application)</a></li><li class="chapter-item expanded "><a href="../../faq/faq-ignore.html"><strong aria-hidden="true">6.13.</strong> Ignore</a></li><li class="chapter-item expanded "><a href="../../faq/faq-uninstall.html"><strong aria-hidden="true">6.14.</strong> Uninstall</a></li><li class="chapter-item expanded "><a href="../../faq/faq-eol.html"><strong aria-hidden="true">6.15.</strong> ClamAV EOL Policy</a></li><li class="spacer"></li></ol></li><li class="chapter-item expanded "><a href="../../community_resources/CommunityResources.html"><strong aria-hidden="true">7.</strong> Community Resources</a></li><li class="spacer"></li><li class="chapter-item expanded "><a href="../../appendix/Appendix.html"><strong aria-hidden="true">8.</strong> Appendix</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../appendix/Terminology.html"><strong aria-hidden="true">8.1.</strong> Terminology</a></li><li class="chapter-item expanded "><a href="../../appendix/CvdPrivateMirror.html"><strong aria-hidden="true">8.2.</strong> Hosting a Private Database Mirror</a></li><li class="chapter-item expanded "><a href="../../appendix/Authenticode.html"><strong aria-hidden="true">8.3.</strong> Microsoft Authenticode Signature Verification</a></li><li class="chapter-item expanded "><a href="../../appendix/FileTypes.html"><strong aria-hidden="true">8.4.</strong> ClamAV File Types and Target Types</a></li><li class="chapter-item expanded "><a href="../../appendix/FunctionalityLevels.html"><strong aria-hidden="true">8.5.</strong> ClamAV Versions and Functionality Levels</a></li></ol></li></ol>
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<h1 class="menu-title">ClamAV Documentation</h1>
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<h1 id="file-type-magic"><a class="header" href="#file-type-magic">File Type Magic</a></h1>
<p>ClamAV's primary mechanism for determining file types is to match the file with a File Type Magic signature. These file type signatures are compiled into ClamAV, and may also be overridden dynamically using the definition founds found in a <code>*.ftm</code> file.</p>
<p>The ClamAV standard signature database includes these definitions in <code>daily.ftm</code>.</p>
<p>The signature format is not too disimilar from NDB body-based signatures.</p>
<p>The format is:</p>
<pre><code>magictype:offset:magicbytes:name:rtype:type[:min_flevel[:max_flevel]]
</code></pre>
<p>Where:</p>
<p><code>magictype</code>: Supported magic types include:</p>
<ul>
<li><code>0</code> - direct memory comparison of <code>magicbytes</code> for file types</li>
<li><code>1</code> - The <code>magicbytes</code> use the body-based content matching <a href="BodySignatureFormat.html">format</a>.</li>
<li><code>4</code> - direct memory comparison of <code>magicbytes</code> for partition types (HFS+, HFSX)</li>
</ul>
<p><code>offset</code>: The offset from start of the file to match against. May be <code>*</code> if <code>magictype</code> is 1.</p>
<p><code>name</code>: A descriptive name for the file type.</p>
<p><code>rtype</code>: Previously detected file type. Usually CL_TYPE_ANY as a wild-card.</p>
<p><code>type</code>: The CL_TYPE corresponding with the file type signature. See the <a href="../../appendix/FileTypes.html">CL_TYPE reference</a> for details.</p>
<p><code>min_flevel</code>: (optional) The minimum ClamAV engine that the file type signature works with. See the <a href="../../appendix/FunctionalityLevels.html">FLEVEL reference</a> for details. To be used in the event that file type support has been recently added.</p>
<p><code>max_flevel</code>: (optional, requires <code>min_flevel</code> field, though the <code>min_flevel</code> number itself can be left empty) The maximum ClamAV engine that the file type signature works with. To be used in the event that file type support has been recently removed or replaced.</p>
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