Malicious PDF — malware analysis report

Static analysis result for SHA-256 f23e8f0b23d82566…

MALICIOUS

PDF

32.9 KB Created: 2021-07-20 03:42:56 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 100994cc578448f8cc85b4399f72b3bc SHA-1: bd43ff3da3f7b7c218952881eb7dbfca1df78e3a SHA-256: f23e8f0b23d82566159305431407982755607235aefd753735a8ab96ac03a02e
82 Risk Score

Malware Insights

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

The PDF document contains a lure for 'free Robux codes' and game hacks, directing users to the malicious URL http://netcdn.tw/app/431946152/free-robux-codes-game-hack. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to exploit user interest in free in-game items to redirect them to potentially malicious content or download further payloads. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9900

Heuristics 4

  • 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 http://netcdn.tw/app/431946152/free-robux-codes-game-hack PDF link annotation
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/free-minecraft-server_GM479516143.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/free-views-on-tiktok_GM835599320.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/get-tiktok-followers-free_GM835599320.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/free-robux-offers_GM431946152.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/promo-codes-for-free-robux_GM431946152.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/coin-master-free-spin-and-coins-links-2021_GM406889139.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/coin-master-free-spin-today_GM406889139.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/minecraft-pe-hack-client_GM479516143.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/free-tiktok-video_GM835599320.pdfIn PDF document text
    • https://www.esmartdigitalcard.com/uploaded_files/userfiles/files/free-robux-gift-card_GM431946152.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00002c41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2C41 22512 bytes
SHA-256: 4f5022b28db80650367fcbad4a300235fa4e567b34916ed5d510cc170455ced2
font_01_sfnt_off00005e6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5E6A 18372 bytes
SHA-256: ebd16bed473c0d10154cd721ddc212c44ce3f73d33b4848c8fd41fc41acf3798