Malicious PDF — malware analysis report

Static analysis result for SHA-256 b79b08496c8edaa1…

MALICIOUS

PDF

35.5 KB Created: 2021-07-03 14:58:56 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-29
MD5: b5da9e83442c22cb6eb875c559c09d36 SHA-1: 40c452772f14bb30d7e196b23aeb8eec159ce703 SHA-256: b79b08496c8edaa13455619a2bbfae93f0bda619476cc29ce5c8f0fac2431264
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-game-hack PDF link annotation
    • https://www.vizyonproduction.com/application/uploads/assets/files/todays-free-spin-and-coin-links_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/earn-free-roblox-jailbreak-money_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/coin-master-free-spins-daily-link-updated_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/how-to-get-gold-cards-on-coin-master-hack_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/roblox-fun-com-free-robux_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/how-to-get-free-clothes-on-roblox-high-school_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/free-minecraft-skin-maker_GM479516143.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/roblox-apps-info-hack-generator_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/free-robux-without-offers_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/free-robux-2021-no-human-verification_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/buy-robux-free_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/roblox-land-free-robux_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/coin-master-free-spin-daily-link_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/free-robux-without-downloading-anything_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/roblox-robux-hack-no-downloading-apps_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/arbx-club-free-robux_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/coin-master-free-spin-2912-2021_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/free-spins-on-coin-master-2021_GM406889139.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/roblox-games-com-free_GM431946152.pdfIn PDF document text
    • https://www.vizyonproduction.com/application/uploads/assets/files/hack-coin-master-online_GM406889139.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_off000033a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x33A9 22804 bytes
SHA-256: fb9768420ad0e99456f0d5d5259f22086c6870718c4ddddf806bb0f2cc26aabf
font_01_sfnt_off000066bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x66BC 18716 bytes
SHA-256: ae86725dd70d168e8b5a24377d7effb3bd88f81667aa3e091abc0f5759eb354b