Physical Security.yml

- cvssv3: 'CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
  priority: 3
  remediationComplexity: 2
  category: Physical Security
  details:
    - references: []
      locale: EN
      title: MIFARE Classic - Authentication by UID only
      vulnType: Pentest
      description: >-
        <p>Each NFC tag has a unique ID (UID). This UID can be read by everyone
        and is not protected in the case of MIFARE Classic tags.<br>Systems can
        be configured to only check the UID as an authentication feature, where
        no validation against data in the tag's encrypted sectors is taking
        place.<br><br>All an attacker would need to do is “touch” an ID tag with
        e.g., a Flipper Zero or other according hardware to fetch the UID. Think
        of standing in an elevator, the keycard on a lanyard, and just walking
        by your target. After successfully fetching the UID, it would be
        possible to impersonate that user granting access to all his resources.
        <br>This might be doors, gates, hotel rooms, a skiing-pass, student ID
        or a printing solution. <br><br>Another way of attacking such weak
        implementations is a brute force attack against the UID. This might
        obviously take a long time, but nevertheless poses a risk.</p>
      observation: <p></p><p></p>
      remediation: >-
        <p>One point to address is user awareness. If an attacker cannot “touch”
        the ID card, it cannot be read. This, however, interferes with the
        corporate policy to always wear your badge visibly to everyone. So at
        least outside of the campus, badges should not be worn visibly.<br>The
        other thing is to check whether the solution is capable of not only
        relying on the UID, but rather data that is stored in one of the secured
        sectors. In this course you need to make sure to use safe technology
        like <em>MIFARE DESFire</em>, as for example the MIFARE Classic
        technology is broken and full of security flaws.</p>
      customFields: []

- cvssv3: 'CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
  priority: 3
  remediationComplexity: 3
  category: Physical Security
  details:
    - references:
        - >-
          [1]
          https://www.researchgate.net/publication/1915327_A_practical_attack_on_the_MIFARE_classic
        - >-
          [2]
          http://www.cs.ru.nl/R.Verdult/Ciphertext-only_Cryptanalysis_on_Hardened_Mifare_Classic_Cards-CCS_2015.pdf
        - '[3] https://github.com/equipter/mfkey32v2'
        - >-
          [4]
          https://www.mifare.net/en/products/chip-card-ics/mifare-classic/security-statement-on-crypto1-implementations/
      locale: EN
      title: Usage of MIFARE Classic technology
      vulnType: Pentest
      description: >-
        <p>In 2008 the proprietary encryption algorithm <em>CRYPTO-1</em>,
        developed by NXP, was completely reverse engineered by the Radboud
        University Nijmegen [1]. <br>In 2009, the MIFARE Classic Offline Cracker
        (MFOC) was released, wrapped around the so called nested attack which
        makes it possible to recover all sector encryption keys when only one
        key is known. <br>Following was the <em>MFCUK-MiFare Classic Universal
        toolkit</em>, which allowed to retrieve a valid key, even if no key was
        known at all.<br>The answer to these flaws was the release of the
        <em>MIFARE Classic EV1</em> tags as well as the MIFARE DESFire tags by
        NXP, which had several security improvements over the original
        implementation.<br>However, in 2015 the <em>hardnested attack [2]</em>
        was published, which allowed to even crack these hardened tags open by a
        side-channel attack.</p><p>As soon as an attacker gets a hold on a
        vulnerable tag, he can recover all keys, access all sectors, tamper with
        the content, and clone the tag.<br>Attack scenarios might include a lost
        tag or stolen tag, a cloned tag or even an inside
        attacker.</p><p>Another way of abuse involves just having the UID of a
        card (read in a second with a Flipper Zero or Proxmark3) and emulate it
        to collect encrypted nonces [3] from a valid reader to later be able to
        offline crack the encryption keys. In some cases this is not sufficient
        and an attacker needs to sniff traffic from a legit card and reader to
        successfully collect the nonces.</p>
      observation: <p></p><p></p>
      remediation: >-
        <p>According to NXP <em>MIFARE Classic</em> cards are no longer
        considered save [4] and should not be used anymore, when it comes to
        managing access rights or other security relevant implementations. The
        most modern successor is <em>MIFARE DESFire</em>. </p>
      customFields: []