Malicious PDF — malware analysis report

Static analysis result for SHA-256 993326ab01e76b29…

MALICIOUS

PDF

35.2 KB Created: 2021-07-05 21:20:00 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-02
MD5: f7a76a5090d1279463f13ce65e698a48 SHA-1: 0993d5e77406803c3283b952c58205081dd74c28 SHA-256: 993326ab01e76b293b65300e138c6b5fdaad0fedba378d8afac3681eff60a50b
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/406889139/how-to-get-free-spins-on-coin-master-without-verification-game-hack PDF link annotation
    • https://loba.com.vn/public/upload/files/gamesyourday-free-robux_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-no-scam-or-hack_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-get-free-robux-without-downloading-any-apps_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-shirt-codes-free-shipping_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-hack-roblox-without-a-app_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-hack-roblox-on-mac-2021_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/best-hack-for-dragon-ball-z-rage-on-roblox_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-hack-that-realy-works_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/arcane-adventures-roblox-14-hack_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-robux-hacker-us_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-free-robux-android_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/coin-master-rewards-2021_GM406889139.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/2021-free-spins-coin-master_GM406889139.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/roblox-the-scary-elevator-red-key-locations-cheat-sheet_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/jak-zrobici-za-free-postaci-w-roblox_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/ruso-icu-roblox-free-robux_GM431946152.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/minecraft-for-chromebook-free_GM479516143.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/free-card-collection-in-coin-master_GM406889139.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/how-to-get-free-minecoins-in-minecraft_GM479516143.pdfIn PDF document text
    • https://loba.com.vn/public/upload/files/robux-generators-that-actually-work_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_002_off000030b4.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x30B4 23224 bytes
SHA-256: f5cda0efe70e927f0a1a30d92d960af84b9754b723b83ce35b0e7d1ba1988fda
font_01_sfnt_off0000651e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x651E 18976 bytes
SHA-256: 3517fa96bcfa360d00a9e909480394bd0858030d7a28ece2362a166d54c1fabc