Malicious PDF — malware analysis report

Static analysis result for SHA-256 83c40f60ffe39fb0…

MALICIOUS

PDF

32.2 KB Created: 2021-07-19 04:43:17 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 285753487c595b4e273a68ba94e7783f SHA-1: 8ebbdf8ab7d81bf4486db563939e80b02abc5cea SHA-256: 83c40f60ffe39fb07b5c5329223e0847b7ae37e0774376b8359dbcd251977855
160 Risk Score

Malware Insights

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

The PDF contains multiple links that redirect to malicious infrastructure, masquerading as free game hacks or generators. The document body explicitly mentions 'Free Robux No Offers' and includes a 'CLICK HERE TO ACCESS ROBUX GENERATOR' call to action, reinforcing the lure. The ML classifier strongly flagged this PDF as malicious, and the embedded URLs are associated with known malicious redirectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9900

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-no-offers-game-hack In PDF document text
    • http://rainbowbuddha.academy/images/roblox-pink-free-robux_GM431946152.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/minecraft-hack-download_GM479516143.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/free-minecraft-accounts-reddit_GM479516143.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/how-to-get-minecraft-for-free-on-ps4_GM479516143.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/tiktok-fans-free_GM835599320.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/robux-hack_GM431946152.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/free-robux-gift-card-codes_GM431946152.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/tiktok-followers-for-free_GM835599320.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/free-robux-without-verification_GM431946152.pdfIn PDF document text
    • http://rainbowbuddha.academy/images/minecraft-free-ios_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
font_00_sfnt_off000029da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x29DA 22584 bytes
SHA-256: c256b98227fa87b2ea25aca2e1c86ec06307425412e4e50a70f5f23980f49f44
font_01_sfnt_off00005c19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5C19 18200 bytes
SHA-256: 9667d64c08376f15d8cfb45c3aacba43ac1d421472699037c9c528d853194b66