Malicious PDF — malware analysis report

Static analysis result for SHA-256 413dd57579e491b2…

MALICIOUS

PDF

35.2 KB Created: 2021-07-06 19:48:04 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 479433b6c25a0ed9ce41372146163b26 SHA-1: 00ccb8810b93205f66bc6a208d0f99a7506f7015 SHA-256: 413dd57579e491b21f60845defb8585fc74043a313a28a44d37f6054a274ce82
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded links that lead to a known malicious redirector, disguised as a 'free generator' or 'game hack'. The document body, though partially corrupted, contains references to these lures and the malicious URL. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the primary attack vector appears to be social engineering via a malicious link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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/406889139/free-spin-coin-master-game-game-hack In PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/how-to-hack-nuclear-tycoon-money-on-roblox_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/noob-vs-pro-vs-hacker-roblox-bee-swarm-simulator_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/is-minecraft-java-edition-free_GM479516143.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-robux-ad_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-roblox-pikachu-accessories-2021_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/coin-master-free-spins-and-coins-daily_GM406889139.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/hack-in-roblox-players-acc-com_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/wwwcoin-master-hack-apk_GM406889139.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-robux-obby_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-money-roblox-pc_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/rblx-city-free-robux_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-robux-pins_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/claimrbx-free-robux_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/rbx-free-robux_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/free-3d-models-for-roblox_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/rise-of-nations-cheats-roblox_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/coin-master-free-spins-hack-iphone_GM406889139.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/coin-master-claim-spins_GM406889139.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/roblox-cheat-codes-list_GM431946152.pdfIn PDF document text
    • http://www.vkinstitute.co.in/uploaded_files/userfiles/files/roblox-com-r_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_off00003423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3423 22696 bytes
SHA-256: 636e1b76c7a4acf3c5dfd9042d2df0e0203486a4ed0047acc0bae7f4337b1afc
font_01_sfnt_off000066b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x66B0 18432 bytes
SHA-256: 85223bd49af77d40a0092bd2c3733620e417d7d5fcdc632707b7c4feb3d04c0e