Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5bd4505a3b7f3e8…

MALICIOUS

PDF

47.8 KB Created: 2021-06-08 19:29:30 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 2afc6c64c5d5639b2881489027e57082 SHA-1: 062061a30506877beb975282c407bbedf3e260d3 SHA-256: b5bd4505a3b7f3e85167e25f46f0e630f0e770596cbbf9b3ba497404d972940c
200 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, specifically pointing to a 'free generator / game hack' lure. The document body, though heavily obfuscated, contains URLs that align with this lure. The presence of a fake CAPTCHA heuristic further supports the social engineering aspect of tricking users into interacting with malicious content. The ML classifier also flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9769

Heuristics 5

  • 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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.tw/app/431946152/roblox-mod-hack-robux-game-hack In PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/free-roblox-gift-card_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/coin-master-free-cards-and-spin-link_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/how-to-get-free-wings-in-roblox-promo-codes_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/free-robux-without-survey_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/robux-link_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/how-to-get-free-robux-easy-2021_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/can-you-give-me-free-robux_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/coin-master-download_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/coin-master-free-spins-whatsapp-link_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/free-coin-master-cards_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/oprewards-login_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/free-girl-hair-roblox_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/roblox-exploit-scripts_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/free-robux-websites-that-actually-work_GM431946152.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/free-minecraft-java-server_GM479516143.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/minecraft-launcher-free_GM479516143.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/coin-master-free-spins-cheats_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/androeed-ru-minecraft_GM479516143.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id/repository/coin-master-hack-fast_GM406889139.pdfIn PDF document text
    • http://www.perpustakaan.unda.ac.id//repository/how-to-hack-a-roblox-account-2021_GM431946152.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00004f0f.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4F0F 26312 bytes
SHA-256: 627db845efee3746a5f99e75a22287d130621fcfc14c296e091e004ac3caeb4a
font_01_sfnt_off00008d23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8D23 2824 bytes
SHA-256: bd082aa73fbb1a8b3bd2e5c998d3d8e31d1dfc71ea36f846af746f69a0d2ab7f
font_02_sfnt_off000096d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x96D7 18692 bytes
SHA-256: 5a8a627943231a3211bf3dbd1083f6058103d4e6f8c31a13846a16fd7d7f919e

Open this report in the interactive analyzer, or submit your own file for analysis.