Malicious PDF — malware analysis report

Static analysis result for SHA-256 512905bd4fb13bc5…

MALICIOUS

PDF

50.9 KB Created: 2021-06-11 00:16:30 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 29fc2bc7b5c753cddbf88cc4dfe45276 SHA-1: d889520c38891a2df44c0390823f3b9534ceae76 SHA-256: 512905bd4fb13bc53b819f2c3a7716f7a43e753f749ea29762d3887062d11959
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document employs a common lure of 'free Robux' and game hacks to entice users to click on external links. The heuristic findings indicate a link farm strategy, with numerous PDFs hosted on external domains, suggesting a potential SEO manipulation or content distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9724

Heuristics 5

  • 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.
  • PDF links to a 'free generator / game hack' redirector high PDF_GAME_HACK_REDIRECT_LURE
    PDF's clickable action targets a redirector of the form /app/<id>/<slug>-game-hack — the landing-page shape of a large SEO 'free spins / generator / game hack' lure family that funnels victims through rotating disposable hosts to a malware/scam payload. The multi-link variants also trip ML/link-farm rules; this catches the single-link variants that otherwise score clean.
  • 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.tw/app/431946152/free-robux-hack-no-confusion-game-hack PDF link annotation
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-get-minecraft-for-free-on-android_GM479516143.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/free-coins-coin-master-2021_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/roblox-free-robux-bots-are-back_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-download-minecraft-for-free-on-iphone_GM479516143.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/free-robux-hacker-us_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-get-robux-for-free-2021_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-can-i-get-free-coinsn-coin-master_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/coin-master-links-free-spins_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/moonactive-coin-master-free-spins_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/www-roblox-com-robux_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-play-minecraft-for-free-on-pc_GM479516143.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-make-a-minecraft-client_GM479516143.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/get-me-robux-for-free_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/tiktok-viewer-free_GM835599320.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/coin-master-free-spain_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/coin-master-free-cards-link_GM406889139.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/free-promo-codes-roblox-body_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/how-to-get-free-robux-on-roblox_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/free-roblox-shirt-templates_GM431946152.pdfIn PDF document text
    • https://www.portalgrandeponto.com.br/public/uploads/galerias/ckeditor/files/haktuts-coin-master-free-spins_GM406889139.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00005490.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x5490 31888 bytes
SHA-256: 1ff1f7bcfe3cf63509d310f5a19f922b48e74f260646ae8785ed6a8b5a435961
font_01_sfnt_off00009a17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9A17 2824 bytes
SHA-256: 94c1b019735d7e491765340abe50b2897410e2ec65ecf141c08bd9f2220897c4
font_02_sfnt_off0000a3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA3C6 18532 bytes
SHA-256: 40e6068ffc4a5c35091d4ca6fedec51ac50aa8e4c0d163b46b92896409341317