Malicious PDF — malware analysis report

Static analysis result for SHA-256 71108c7a89d4f85c…

MALICIOUS

PDF

35.3 KB Created: 2021-06-19 15:59:39 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 6774eb4d76d7b0c58f6b8810628b83c5 SHA-1: 2d3e44305f0bbcc8ee2763b6aaceb5981da35892 SHA-256: 71108c7a89d4f85c5c5e583bfee1eef393f0382f14bf72e69b07acb2c6d54827
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a large number of external links, many of which are SEO-optimized and point to other PDF files. The primary URL, http://netcdn.co/app/431946152/free-cool-girl-clothes-on-roblox-game-hack, suggests a lure for free in-game items, likely leading to further malicious content or scams. The ML classifier strongly indicated maliciousness, supporting the conclusion that this is a link farm designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://netcdn.co/app/431946152/free-cool-girl-clothes-on-roblox-game-hack PDF link annotation
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/how-to-get-free-robux-2021_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/coin-master-free-daily-spins-and-coins_GM406889139.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/descargar-coin-master-hack_GM406889139.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/coin-master-tiradas-gratis-link_GM406889139.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/how-to-get-more-followers-on-tiktok-free_GM835599320.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/free-paypal-accounts-with-money-for-roblox-with-card-code_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/coin-master-free-link-app_GM406889139.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/coin-master-gold-cards-hack-english_GM406889139.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/minecraft-noob-vs-pro-vs-hacker-vs-god_GM479516143.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/how-to-make-your-own-minecraft-pe-server-for-free_GM479516143.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/roblox-free-robux-no-verification_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/robux-gift-card-free_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/free-tiktok-followers-quora_GM835599320.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/free-roblox-toy-codes-2021_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/games-that-give-free-robux_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/how-to-download-minecraft-for-free-on-iphone_GM479516143.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/roblox-play-now-for-free_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/free-robux-generator-for-roblox-2021_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/how-to-change-your-roblox-username-for-free_GM431946152.pdfIn PDF document text
    • https://comunidaddeatencion.argentina.gob.ar/ckfinder/userfiles/files/coin-master-official-page_GM406889139.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00003274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3274 22736 bytes
SHA-256: cd5b1c0aa39c65e8d89f0364eba7e3fda6cd54a1d661e35c8e5687e092e293da
font_01_sfnt_off00006530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6530 19040 bytes
SHA-256: 888a7f39ea40caa73872a851fcf7674a6ceac1b944744612febff994df06fd66