Malicious PDF — malware analysis report

Static analysis result for SHA-256 18a91c4bb72badc9…

MALICIOUS

PDF

30.5 KB Created: 2021-07-23 02:13:49 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 23a0def32a1749676671ed8a32d41a63 SHA-1: 5026f66a1a7e1961736d6a9297ddf035f042fec5 SHA-256: 18a91c4bb72badc9594b87ad645f5ed188831c765d165029986d1776dd016ebe
130 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a lure for a 'Free Robux Generator' which redirects to a known malicious URL. This indicates a phishing or scam attempt designed to trick users into visiting a potentially harmful site. No scripts were extracted, but the embedded URL is the primary indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier clean score 0.0483

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-generator-no-human-verification-2021-game-hack In 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_off0000203e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x203E 22436 bytes
SHA-256: 55ca9956efeb14fe28adf11ffd4db66dd0b12d35670a6872f926754cc7aed759
font_01_sfnt_off00005234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5234 19448 bytes
SHA-256: c4f235c6325a062dfb1dc9d53c980481f8635b4baeb4de16fff816f4c5634972