Malicious PDF — malware analysis report

Static analysis result for SHA-256 f72a1bbc8ef9fa1e…

MALICIOUS

PDF

34.5 KB Created: 2021-07-03 14:21:57 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 7835c3dae947a3a44661e25233b3d884 SHA-1: f6e6b69e46fb130736789d5875692533a1159f9c SHA-256: f72a1bbc8ef9fa1e203d96044125ffe2b9da413b4ea76ab0d4742d865f6e3492
102 Risk Score

Malware Insights

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

The PDF document contains numerous links to external websites, many of which are structured as SEO-optimized PDF links. The document body and extracted URLs suggest a lure for free in-game items or currency for games like Coin Master and Roblox. The ML classifier also flagged this PDF as malicious with high confidence.

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.tw/app/406889139/how-to-generate-free-coin-master-spin-game-hack
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-minecraft-svg-cutting-files_GM479516143.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/coin-master-daily-free-spins-and-coins_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/tower-of-hell-roblox-hack_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/how-to-get-free-hair-in-roblox_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/coin-master-free-coins-and-spins-link_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-roblox-toy-codes_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-spin-coin-master-link-2021_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/how-to-download-minecraft-for-free-ios_GM479516143.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-spins-on-coin-master-iphone_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-robux-no-human-verification-or-survey_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/coin-master-daily-free-spins-link-today-haktuts_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/coin-master-hack-tool-v1-9-download_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/real-free-spins-for-coin-master_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-robux-giveaway-live-stream_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/coin-master-50-spin-link_GM406889139.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/roblox-hack-client_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-minecraft-website_GM479516143.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/free-robux-stream_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/20210-robux_GM431946152.pdf
    • http://kmh.ddnsthailand.com/ckfinder/userfiles/files/master-coin-free_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000312d.bin
8daad64c5adfab4cb30f6ba89de6c26c1ea89931831d3a103d3723c26e0a9877
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x312D 22800 bytes
font_01_sfnt_off0000641d.bin
44149cbd1419f5cddd2185958f28928906a990b98f16256b2ecbc419de034d9f
pdf-font-stream PDF embedded font (sfnt) at offset 0x641D 18336 bytes