Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d4dba247b725345…

MALICIOUS

PDF

35.4 KB Created: 2021-07-05 02:55:24 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 965fd623ff60783fec1cfc27bfccf6b5 SHA-1: 0b9f572748b5ed9ea4f56207a2a46643366d38cd SHA-256: 2d4dba247b725345d647af8ae9693f342bbe31c9440c6d9942632b20886c95c7
220 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a malicious redirector, specifically luring users with 'free generator / game hack' content. The primary malicious URL identified is http://netcdn.tw/app/406889139/free-coins-and-spins-coin-master-game-hack, which is linked to known malicious infrastructure. The document body also contains this URL and other links that appear to be part of an SEO link farm, suggesting an attempt to attract users through search engines.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • PDF links to a 'free generator / game hack' redirector critical 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. CRITICAL on its own: the /app/<id>/<slug>-game-hack path shape is unambiguous scam infra, and the host rotates so a host-list match can't be relied on.
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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/406889139/free-coins-and-spins-coin-master-game-hack In PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-banned_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-instant-catalog-item-roblox_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-roblox-gift-card_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-do-you-get-free-robux-on-roblox-2021_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-gift-card-print_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-no-verification-no-download-2021_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/minecraft-free-download-pc_GM479516143.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-free-spins-hack_GM406889139.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/cheat-adopt-me-roblox_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/ex7-roblox-hack-free_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/haktuts-coin-master-free-spin-today_GM406889139.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/tiktok-free-view-mobile_GM835599320.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-com-no-verification_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-web-site-2021_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/google-how-do-you-get-free-robux_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-just-download-a-game_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/free-robux-websites-that-actually-work_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/coin-master-free-daily-spins-link_GM406889139.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/how-to-have-200-robux-free-robux_GM431946152.pdfIn PDF document text
    • https://gzhi.govvrn.ru/uploads/ckfinder/userfiles/files/minecraft-games-to-play-for-free_GM479516143.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
stream_002_off0000332c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x332C 23220 bytes
SHA-256: 6721202b95cc435940ce03ad54a5e21014b25d769f25782bf73e42510645b77d
font_01_sfnt_off00006794.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6794 18348 bytes
SHA-256: c90f632020bcb1e728f62a43997badda2860e0d329262e99dedc1f8a12c39115