Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0df9913fa3b1014…

MALICIOUS

PDF

36.4 KB Created: 2021-07-04 04:40:28 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 3a87caa632085f4f2bd669d85914bd50 SHA-1: 519e681a6ebd72fa5d095f2870a9d2abbacb8cd2 SHA-256: f0df9913fa3b1014361ec0a8badaf76f32c7d34792c1b6dff87a22f2f7eefe37
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a lure for "Robux Gift Card Free" and embeds a significant number of external links, many pointing to other PDF files. One of these links, http://netcdn.tw/app/431946152/robux-gift-card-free-game-hack, is flagged as a potential malicious URI. The presence of a link farm and the ML classifier's high confidence score indicate a malicious intent, likely to redirect users to a malicious download or phishing site.

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/431946152/robux-gift-card-free-game-hack
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-to-get-free-roblox-items_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-daily_GM406889139.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-to-get-a-free-robux-in-roblox_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/roblox-prison-life-hack-free-download_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-hack-tool-for-pc_GM406889139.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/roblox-welcome-to-bloxburg-money-cheat-august-2021_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/one-punch-man-unleashed-roblox-hack-cheat-engine_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-claim-free-spins_GM406889139.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/get-free-followers-on-tiktok_GM835599320.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-girl-hair-roblox_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-to-get-gojirasaurus-free-ancient-earth-roblox_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-34-6-hack_GM406889139.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/hack-roblox-prion-life_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/are-there-any-actual-robux-cheats-reddit_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/minecraft-free-download-linux_GM479516143.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/roblox-dominus-free-2021_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/make-your-own-minecraft-server-free_GM479516143.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/hack-robux-gratis-como-tener-robux-gratis-2021_GM431946152.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-to-make-a-minecraft-bedrock-server-for-free_GM479516143.pdf
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-app-free-download_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000362a.bin
3ff7c0352e6a5d127f25b0303fa7299c9c7e8bbe4b4f4ae0767d5ee7b64c21af
pdf-font-stream PDF embedded font (sfnt) at offset 0x362A 22776 bytes
font_01_sfnt_off0000692e.bin
2ea37c508b0c91132d1ae13c4ee486db57383bf0a0a064ac7651587d02fc5b1e
pdf-font-stream PDF embedded font (sfnt) at offset 0x692E 19112 bytes