Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8cd0a408d697ef9…

MALICIOUS

PDF

33.7 KB Created: 2021-07-19 13:33:21 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 520c8eb369915bf1894b530fa3ffcab8 SHA-1: 80f62d9f12d139f7734104282ad9f474567c6f00 SHA-256: b8cd0a408d697ef952514c55e7d36d9433d2cbab3ecb7b713bc6ef83f99d8ecb
160 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 targeting users with lures for free Robux and game hacks. The primary malicious URL, http://netcdn.tw/app/431946152/free-robux-legit-game-hack, is embedded within the document body and is also referenced by critical heuristic firings. The document's structure and content suggest an attempt to trick users into visiting this malicious site, likely to download further malware or engage in phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

Heuristics 4

  • 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.
  • 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/431946152/free-robux-legit-game-hack In PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/haktuts-coin-master-free-spin-link_GM406889139.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/how-to-get-minecraft-for-free-on-chromebook_GM479516143.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/free-robux-offers_GM431946152.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/free-minecraft-skin-packs_GM479516143.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/free-spins-coin-master-app_GM406889139.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/you-promised-my-son-free-robux_GM431946152.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/how-to-host-a-minecraft-server-for-free_GM479516143.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/free-spin-coin-master-link-2021_GM406889139.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/free-spins-for-coin-master-app_GM406889139.pdfIn PDF document text
    • https://www.yatatravel.com/uploaded_files/userfiles/files/coin-master-free-stuff_GM406889139.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_off00002d48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2D48 22956 bytes
SHA-256: f0eb910b7de9cdac64d2e2e214f0bad6254cab986f1303abe14be6e295a61b5f
font_01_sfnt_off0000608d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x608D 18712 bytes
SHA-256: 0a3bb92d146b122749d57d36755b29a560cd1c032c54bb08c637f56f67b3a8e8