Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f4589d705b7d741…

MALICIOUS

PDF

45.5 KB Created: 2021-06-10 12:10:06 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 3fa0e533b235e342ea6440209ee9b327 SHA-1: 15260213dab84f085fcb37a3083e7e286a35f5b8 SHA-256: 8f4589d705b7d7410ea1e627eb5d4f999421b1c294008c58dbb5f085672d8373
142 Risk Score

Malware Insights

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

The PDF document contains a fake CAPTCHA lure, designed to trick users into interacting with the document. It also hosts a large number of external links, many of which appear to be SEO-optimized PDF links, suggesting a link farm or content distribution network. The primary URL points to a resource that likely serves as a download or redirect for a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9864

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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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-pastebin-2021-game-hack
    • http://gieldapracy.pl/images/roblox-gift-codes-free_GM431946152.pdf
    • http://gieldapracy.pl/images/how-to-download-minecraft-for-free-on-iphone_GM479516143.pdf
    • http://gieldapracy.pl/images/coin-master-hack-spins-android_GM406889139.pdf
    • http://gieldapracy.pl/images/coin-master-gold-cards-free_GM406889139.pdf
    • http://gieldapracy.pl/images/free-robux-hack-no-human-verification-or-survey_GM431946152.pdf
    • http://gieldapracy.pl/images/free-robux-hack-no-human-verification_GM431946152.pdf
    • http://gieldapracy.pl/images/coin-master-claim-free-spins_GM406889139.pdf
    • http://gieldapracy.pl/images/roblox-free-hair-girl_GM431946152.pdf
    • http://gieldapracy.pl/images/download-coin-master-hack-tool-v1-9_GM406889139.pdf
    • http://gieldapracy.pl/images/coin-master-hack-ios-no-jailbreak_GM406889139.pdf
    • http://gieldapracy.pl/images/get-free-robux-com_GM431946152.pdf
    • http://gieldapracy.pl/images/coin-master-spin-rewards_GM406889139.pdf
    • http://gieldapracy.pl/images/coin-master-free-spins-2021-ios_GM406889139.pdf
    • http://gieldapracy.pl/images/roblox-arsenal-hack_GM431946152.pdf
    • http://gieldapracy.pl/images/free-robux-please_GM431946152.pdf
    • http://gieldapracy.pl/images/roblox-script-hacks_GM431946152.pdf
    • http://gieldapracy.pl/images/coin-master-hack-https-coinms-net_GM406889139.pdf
    • http://gieldapracy.pl/images/coin-master-rewards-free-spins_GM406889139.pdf
    • http://gieldapracy.pl/images/how-to-get-free-robux-form-inspect_GM431946152.pdf
    • http://gieldapracy.pl/images/free-tiktok-likes-app_GM835599320.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00004ffe.bin
963330411c8514c2cb6305b88a737c5fbfe1b736aa45753a4cad938a3e021b30
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4FFE 26412 bytes
font_01_sfnt_off00008ce0.bin
2aa8d4717cbc9ae3afa6777cfaeea923a37da0297ca8e4950d3b8cc82c5640f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x8CE0 19024 bytes