Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc231ef42ec79278…

MALICIOUS

PDF

35.0 KB Created: 2021-06-23 03:28:01 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 65230c991fd0c215a7aab5d278b76f8a SHA-1: a9e1bacbbb825d849c3d6208b958b4f045e836ba SHA-256: fc231ef42ec792782843318322e17c78a98710e127acbad10231adafcfa3801c
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of external links, many of which are related to game cheats and exploits, suggesting a lure for users to download malicious content. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, and the ML classifier strongly flagged this PDF as malicious. The document body and extracted URLs point towards a scam or phishing attempt related to popular online games.

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/cheating-on-roblox-girlfriend-game-hack
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-robux-hacker-us_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/does-roblox-sense-cheat-engine_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/tiktok-free-view-jelly-fruit_GM835599320.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/roblox-com-games-referrer-roblox-player_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/how-to-get-free-hats-on-roblox_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-robux-without-doing-anything_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-100-robux_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/coin-master-400-spin-link-hack_GM406889139.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-coins-and-spins-link-for-coin-master_GM406889139.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-roblox-email_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/rbx-roblox_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-robux-with-no-verification-2021_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/como-distruir-juegos-en-roblox-si-hack_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/coin-master-apk-mod-free-download_GM406889139.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/if-everything-on-roblox-was-free_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/cute-free-roblox-clothes_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/alsotheking-roblox-hacker_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-code-for-call-of-duty-ww2-roblox_GM431946152.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-coin-master-credit_GM406889139.pdf
    • http://www.med-aid.vn/ckfinder/userfiles/files/free-spins-coin-master-unlimited_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000031a3.bin
7d7eb5d3a56d334e7eb1daffcb4c9267eb110a94267d9d6d10daea099409804d
pdf-font-stream PDF embedded font (sfnt) at offset 0x31A3 22524 bytes
font_01_sfnt_off000063d7.bin
e9ee66d8c5cf1561e45c350bb6f95c7cbb51ad6f65fc792f43add20f7a250029
pdf-font-stream PDF embedded font (sfnt) at offset 0x63D7 19048 bytes