Malicious PDF — malware analysis report

Static analysis result for SHA-256 abfb0261287c10c6…

MALICIOUS

PDF

34.6 KB Created: 2021-07-19 13:42:39 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 5d77f7c28dd0a92ba0ad79efd03a9423 SHA-1: 44a0ee38bd2e0e0fd9e73273a4e5cdd1ccd8276b SHA-256: abfb0261287c10c64fb8971311f4d8c174bd43f27b39fa1b8430d3f87a737c58
160 Risk Score

Malware Insights

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

The PDF contains multiple links, including one to 'netcdn.tw', which is flagged as malicious redirector infrastructure. The document body and embedded links promote 'free Robux' and 'game hacks', a common lure for phishing or malware distribution. The ML classifier also strongly indicated maliciousness. The embedded links likely serve to download a second-stage payload or redirect to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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-without-downloading-apps-game-hack In PDF document text
    • http://grahambettsmotors.com/images/coin-master-free-daily-spins_GM406889139.pdfIn PDF document text
    • http://grahambettsmotors.com/images/free-robux-no-verification-2021_GM431946152.pdfIn PDF document text
    • http://grahambettsmotors.com/images/free-followers-on-tiktok_GM835599320.pdfIn PDF document text
    • http://grahambettsmotors.com/images/free-spins-for-coin-master-game_GM406889139.pdfIn PDF document text
    • http://grahambettsmotors.com/images/how-to-setup-a-minecraft-server-for-free_GM479516143.pdfIn PDF document text
    • http://grahambettsmotors.com/images/coin-master-free-spins-and-coins-2021_GM406889139.pdfIn PDF document text
    • http://grahambettsmotors.com/images/free-robux-without-verification-2021_GM431946152.pdfIn PDF document text
    • http://grahambettsmotors.com/images/rblx-city-free-robux_GM431946152.pdfIn PDF document text
    • http://grahambettsmotors.com/images/how-do-i-get-free-robux_GM431946152.pdfIn PDF document text
    • http://grahambettsmotors.com/images/blox-fish-free-robux_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_off00002e7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2E7C 22380 bytes
SHA-256: 8897a9dc33c32269a9c9472c818f8f37b680d51bec6b2a88c150587d398a202b
font_01_sfnt_off00006003.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6003 20060 bytes
SHA-256: a8fbfe7f7d9ee5c6d1e0a9d54f6a8f2618b4750cae31927e831424281ea5393b