Malicious PDF — malware analysis report

Static analysis result for SHA-256 cafb91dc4aa7c391…

MALICIOUS

PDF

44.1 KB Created: 2021-05-19 19:37:48 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: f2f4ce1f6c61751049477636cb8dec01 SHA-1: 1f05103f3e4ae16d08308512b835bb54b796ec2f SHA-256: cafb91dc4aa7c3912974affa75f90cca2c9e54889091a2f351366b1498158d25
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded links to external PDF files, suggesting a link farm or SEO spamming operation. The ML classifier strongly indicated maliciousness, and the presence of a 'download button' heuristic further supports a deceptive user interaction. The primary IOCs are the URLs pointing to these external PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://netcdn.xyz/app/431946152/boost9-com-roblox-hack-game-hack
    • http://www.furuihp.com/Public/upload/editorfiles/free-spins-for-coin-master-hack_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/http-bitly-coin-master-free-2021-spins_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/how-to-earn-robux-by-playing-games_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/free-roblox-accounts-2021-with-robux_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/how-do-you-get-free-food-in-coin-master_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/master-game_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/haktuts-coin-master-free-spin-link_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/20210-robux_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/free-generator_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/coin-master-free-coins-link-facebook_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/how-to-get-free-gold-cards-on-coin-master_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/free-robux-hacker-us_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/how-to-hack-roblox-for-robux_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/coin-master-daily-spins-and-coins_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/coin-master-free-spins-and-coins-2021_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/free-coin-master-spins-blog_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/game-give-free-robux_GM431946152.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/minecraft-wurst-client_GM479516143.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/coin-master-free-pet-food_GM406889139.pdf
    • http://www.furuihp.com/Public/upload/editorfiles/real-coin-master-hacks_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004b5f.bin
06d6321c7d5c9660d15f7f93164c974b5a9a816a24dfa297e4b63ae15f7974c6
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4B5F 26940 bytes
font_01_sfnt_off000088c9.bin
116e3350f892353559a46e1e2dd8dd97ba265176f89098854de85373f70222e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x88C9 18708 bytes