Recovering the master key from RAM to break Android's file-based encryption (2021)

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  "title": "Recovering the master key from RAM to break Android's file-based encryption (2021)",
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  "url": "https://www.sciencedirect.com/science/article/pii/S266628172100007X"
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{
  "author": "Author links open overlay panelTobias Groß, Marcel Busch, Tilo Müller",
  "date": null,
  "description": "As known for a decade, cold boot attacks can break software-based disk encryption when an attacker has physical access to a powered-on device, includi…",
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  "publisher": "ScienceDirect",
  "title": "One key to rule them all: Recovering the master key from RAM to break Android’s file-based encryption",
  "url": "https://www.sciencedirect.com/science/article/pii/S266628172100007X"
}

{
  "url": "https://www.sciencedirect.com/science/article/pii/S266628172100007X",
  "title": "One key to rule them all: Recovering the master key from RAM to break Android's file-based encryption",
  "description": "View PDFUnder a Creative Commons licenseopen accessAbstractAs known for a decade, cold boot attacks can break software-based disk encryption when an attacker has physical access to a powered-on device,...",
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  "content": "<div><div><div><ul><li><a target=\"_blank\"><svg height=\"20\"></svg><span><span><span>View <strong>PDF</strong></span></span></span></a></li><li></li></ul></div><div><article><div><p><a target=\"_blank\" href=\"https://www.sciencedirect.com/journal/forensic-science-international-digital-investigation\" title=\"Go to Forensic Science International: Digital Investigation on ScienceDirect\"><span><span><img src=\"https://sdfestaticassets-us-east-1.sciencedirectassets.com/prod/b64013ec63c69e3d916174cbebae89d65b2419e1/image/elsevier-non-solus.png\" alt=\"Elsevier\" /></span></span></a></p><p><a target=\"_blank\" href=\"https://www.sciencedirect.com/journal/forensic-science-international-digital-investigation/vol/36/suppl/S\"><span><span><img src=\"https://ars.els-cdn.com/content/image/1-s2.0-S2666281721X00030-cov150h.gif\" alt=\"Forensic Science International: Digital Investigation\" /></span></span></a></p></div><div><p><span>Under a Creative Commons </span><a href=\"http://creativecommons.org/licenses/by-nc-nd/4.0/\" target=\"_blank\"><span><span>license</span><svg height=\"20\"></svg></span></a></p><p><span></span>open access</p></div><div><h2>Abstract</h2><div><p>As known for a decade, cold boot attacks can break software-based disk encryption when an attacker has physical access to a powered-on device, including Android smartphones. Raw memory images can be obtained by resetting a device and rebooting it with a malicious boot loader, or—on systems where this is not possible due to secure boot or restrictive BIOS settings—by a physical transplantation of RAM modules into a system under the control of the attacker. Based on the memory images of a device, different key recovery algorithms have been proposed in the past to break <em>Full Disk Encryption</em> (<em>FDE)</em>, including BitLocker, dm-crypt, and also Android's FDE. With Google's switch from FDE to <em>File-based Encryption (FBE)</em> as the standard encryption method for recent Android devices, however, existing tools have been rendered ineffective. To close this gap, and to re-enable the forensic analysis of encrypted Android disks, given a raw memory image, we present a new key recovery method tailored for FBE. Furthermore, we extend <em>The Sleuth Kit (TSK)</em> to automatically decrypt file names and file contents when working on FBE-enabled EXT4 images, as well as the <em>Plaso</em> framework to extract events from encrypted EXT4 partitions. Last but not least, we argue that the recovery of master keys from FBE partitions was particularly easy due to a flaw in the key derivation method by Google.</p></div></div><ul><li></li><li></li></ul><div><h2>Keywords</h2><p><span>Android</span></p><p><span>EXT4</span></p><p><span>File-based encryption (FBE)</span></p><p><span>Disk forensics</span></p><p><span>Memory forensics</span></p><p><span>Cold boot attacks</span></p></div><section><h2>Cited by (0)</h2></section><p><span>© 2021 The Authors. Published by Elsevier Ltd.</span></p></article></div></div></div>",
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  "ttr": 49,
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