Malicious PDF — malware analysis report

Static analysis result for SHA-256 986e765082ca9519…

MALICIOUS

PDF

45.9 KB Created: 2021-06-03 09:28:50 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 8fc00a1e679f658d1cdcec39f24afeec SHA-1: e53ed46d0815363d37d455b5cf084ffc66fa9b2f SHA-256: 986e765082ca9519ea1b8c4b9156558215c75a20587fc8582c3804645f5d47c0
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to a redirector hosted on 'netcdn.online' which is flagged as malicious and associated with game hack lures. The document body, though partially corrupted, contains text related to 'Free Robux By Watching Ads' and a URL pointing to a similar lure. The presence of embedded URLs and the specific heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9864

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 https://netcdn.online/app/431946152/free-robux-by-watching-ads-game-hack In PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/get-free-robux-com_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-daily-free-spins-link-download_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-daily-free-spins-link-2021-today_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/minecraft-pc-download-free-full-version_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-100-spin_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-coins-link_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-spins-and-coins-coin-master_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-link-2021-download_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-and-coins-haktuts_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-online-games-like-minecraft_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-robux-only-username-no-human-verification_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/how-to-hack-minecraft_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-roblox-clothes_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-ios_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-2021_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/roblox-its-free_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-coin-master-spins_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/kachifpro_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/easy-robux-com_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-link-today-instagram_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
stream_004_off00004da4.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4DA4 28308 bytes
SHA-256: 5e65a11770fb9e0187610f8cb7d57ef848e9401de86647d56ef3ee46ff12f3a8
font_01_sfnt_off00008d14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8D14 19472 bytes
SHA-256: 06b7c2c04a08988b26013261e09f65c94c24f523f4ae9df4e6f4943f7c42b6f1