Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b0f22fd1abe4986…

MALICIOUS

PDF

45.9 KB Created: 2021-06-08 11:09:38 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-31
MD5: 4b0601a370223c3d649bbd99adb3cb25 SHA-1: 564efed4304e3fb0f35ce19e59e88550e77af076 SHA-256: 4b0f22fd1abe498680f90ff003c7817e754344a0414f9cde54382c0d8b3cd146
180 Risk Score

Malware Insights

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

The PDF contains a malformed stream and links to known malicious redirector infrastructure, specifically promoting a 'Roblox Mod Apk Unlimited Robux' download. This suggests an attempt to exploit user interest in game cheats to deliver a malicious payload. While no scripts were explicitly extracted, the PDF structure and embedded links strongly indicate a malicious redirector designed to lead users to potentially harmful content or downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9864

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.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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-apk-unlimited-robux-2021-download-free-game-hack In PDF document text
    • http://muslib.unmus.ac.id//repository/today-free-spin-coin-master_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/best-way-to-get-free-robux_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/client-minecraft_GM479516143.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/games-that-can-be-hacked_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/download-coin-master-hack_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/coin-master-free-spins-that-really_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/coin-master-daily-free-spins-blog_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/robux-free-c_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/coin-master-sound-daily-free-spins-link-today_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/hack-coin-master-dzooka_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/earn-roblox_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/how-to-get-free-spins-on-coin-master-2021-iphone_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/coin-master-free-spin-trick_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/roblox-promo-codes-free-robux_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/50-free-spins-coin-master_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/how-do-you-get-free-robux-without-doing-anything_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/free-robux-no-gift-card_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/free-robux-promo-codes-2021_GM431946152.pdfIn PDF document text
    • http://muslib.unmus.ac.id//repository/coin-master-free-spin-and-coins-links-2021_GM406889139.pdfIn PDF document text
    • http://muslib.unmus.ac.id/repository/free-back-accessories-roblox_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
stream_004_off00005022.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x5022 25124 bytes
SHA-256: beb833e06dc189449dfdb571290bdee1ea4bbb6f1994a8909f3d0a459feae490
font_01_sfnt_off00008aa3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8AA3 20436 bytes
SHA-256: 211f56aabe357c4cb1af6c700f8d1a81b61729ee64fcd70bca1ef69111615677

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