Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef52a2a51d96ef83…

MALICIOUS

PDF

41.9 KB Created: 2021-05-14 08:26:15 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: d017ca8f0081402424b7d0cb2ffe6612 SHA-1: 71082a34b7bf75a35b18c7b8efd2fa427e6cf200 SHA-256: ef52a2a51d96ef831f4d79f927229858e689ef4ddee1d2ace3920190fd433e31
102 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are structured as SEO-optimized PDF links, suggesting a link farm designed to attract users searching for game cheats and hacks. The ML classifier strongly indicated maliciousness, and the presence of a download button lure further supports a malicious intent. The primary goal appears to be directing users to download potentially harmful files from the linked domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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/instantrobux-game-hack
    • http://huounaixunghe.com/images/free-robux-without-human-verification-2021_GM431946152.pdf
    • http://huounaixunghe.com/images/hack-coin-master-site-rssingcom_GM406889139.pdf
    • http://huounaixunghe.com/images/free-robux-generator-no-verification_GM431946152.pdf
    • http://huounaixunghe.com/images/how-to-hack-someone-on-roblox_GM431946152.pdf
    • http://huounaixunghe.com/images/minecraft-windows-10-free-code_GM479516143.pdf
    • http://huounaixunghe.com/images/free-minecraft-texture-packs_GM479516143.pdf
    • http://huounaixunghe.com/images/how-to-get-free-roebucks_GM431946152.pdf
    • http://huounaixunghe.com/images/free-coins-and-spins-in-coin-master_GM406889139.pdf
    • http://huounaixunghe.com/images/unlimited-spin-coin-master-hack_GM406889139.pdf
    • http://huounaixunghe.com/images/blogger-coin-master-free-spins_GM406889139.pdf
    • http://huounaixunghe.com/images/real-free-spins-for-coin-master_GM406889139.pdf
    • http://huounaixunghe.com/images/free-coins-coin-master-link_GM406889139.pdf
    • http://huounaixunghe.com/images/how-to-hack-into-someones-roblox-account_GM431946152.pdf
    • http://huounaixunghe.com/images/2021-free-spins-coin-master_GM406889139.pdf
    • http://huounaixunghe.com/images/how-to-change-your-roblox-username-for-free_GM431946152.pdf
    • http://huounaixunghe.com/images/coin-master-today_GM406889139.pdf
    • http://huounaixunghe.com/images/coin-master-32-android-mod-hack-apk-download_GM406889139.pdf
    • http://huounaixunghe.com/images/free-spins-coin-master-2021-today_GM406889139.pdf
    • http://huounaixunghe.com/images/free-robux-generator-2021-no-survey_GM431946152.pdf
    • http://huounaixunghe.com/images/free-roblox-groups_GM431946152.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004878.bin
2dac16d57e163775dad5f303f66908da054d2f430b7c270fa5cc4a6f034c489f
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4878 24692 bytes
font_01_sfnt_off00008174.bin
4d77632c85c001e266779ad9698d54220e11b78bd17d8b0f085f3dc4dd17180b
pdf-font-stream PDF embedded font (sfnt) at offset 0x8174 18184 bytes