Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c1b3a8f6da9c78…

MALICIOUS

PDF

41.1 KB Created: 2021-04-29 03:21:33 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-15
MD5: dae67160004aac3d499efbe581d5b0d5 SHA-1: 136551c805c1e93ccd1f50d7d0af5fb40bc5e682 SHA-256: 28c1b3a8f6da9c7855327a551c710540d7f8ccd74640b3e1ac055589b4f150a9
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links, including one that redirects to known malicious infrastructure associated with 'free Robux' and game hacks. The ML classifier also flagged this PDF as malicious. The embedded links and the lure suggest an attempt to redirect users to potentially harmful websites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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.xyz/app/431946152/free-robux-number-game-hack In PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/how-to-get-your-robux-back-without-hacking-or-buying.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/case-clicker-cheats-roblox.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/roblox-sword-fight-on-the-heights-original-how-to-hack.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/how-to-hack-arsenal-roblox.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/how-to-hack-someone-in-roblox-on-ipad.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/roblox-admin-hack-2021-november.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/site-robux-free.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/roblox-free-tix-hack.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/blue-boy-hack-roblox.pdfIn PDF document text
    • https://www.tiendagrouppln.com/ckfinder/userfiles/files/free-games-to-download-like-roblox.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_003_off0000412b.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x412B 27944 bytes
SHA-256: d71f5769cd422293dfe0de6807240a2751aaf754138b82cd8a4fe300bc096669
font_01_sfnt_off00007f0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7F0F 18276 bytes
SHA-256: 440595cc9879c2064447608cc896071aecf94c55b2192abb04a6d5912b522649