Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bbf397b6a09cfb8…

MALICIOUS

PDF

34.4 KB Created: 2021-07-08 21:54:17 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 49579040ccdca48fce12e235e57f5a76 SHA-1: 57030ed522e921e34bceb61c15a723362ecf030a SHA-256: 4bbf397b6a09cfb88bf46ec4d0b4dc27d33148fbb465580a1300d6bba47ca5aa
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, routes users through malicious redirector infrastructure and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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.
  • PDF links to a 'free generator / game hack' redirector high 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.
  • 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 http://netcdn.tw/app/431946152/free-robux-generator-com-roblox-hack-game-hack PDF link annotation
    • https://loba.com.vn/public/upload/files/coin-master-free-coins-hack_GM406889139.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-generator-no-verification_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-skins-boy-free_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-make-a-cheat-on-roblox-roblox-studio-2021_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/body-building-roblox-weightlifting-hack_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-without-verification-or-survey_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-no-human-vetifycation_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/cool-free-roblox-outfits_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-be-a-builders-club-in-roblox-free_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/hawt-sauce-hack-roblox_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-2021-robux_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/freer-tiktok_GM835599320.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/can-you-still-get-minecraft-windows-10-for-free_GM479516143.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-cheat-on-roblox-2021_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-come_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/ben-10-universal-showdown-cheats-roblox_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-get-free-robux-2021_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-spins-coin-master-november-2021_GM406889139.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/como-hackear-roblox-android_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-free-card-codes-2021_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_off00002ef3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2EF3 22344 bytes
SHA-256: 5b0cafd6d32b272c9529708de789a96492ac6e03537fcf68f19222abafc05dc8
font_01_sfnt_off0000609a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x609A 19324 bytes
SHA-256: b5fe64a349a1260a8bf1e39cb434a35d84e03f20b24c2703f62dd6d7df3547b9