Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8271564f2756540…

MALICIOUS

PDF

84.9 KB Created: 2021-09-06 16:46:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fb94f3c695ce4eb3d687f0659490350c SHA-1: f25cabdf802e2dfac99c8a478a5ae0e7eb6099bc SHA-256: f8271564f2756540ae94f882521aca6669e7ee1dc634b71a75503abea1d3d280
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised upload storage or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://praguetransfer.com/files/file/67048846850.pdf In PDF document text
    • https://srldirect.com/ckfinder/userfiles/files/66264485855.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/ninibasikixoguxili.pdfIn PDF document text
    • http://pazzo.jp/js/upload/files/6443466257.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/39d8994619d1a1feaae30dd203d5feac/jurawovemupevozigox.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/17537895623.pdfIn PDF document text
    • https://kurashi-kyoiku.com/cms/dat/upimg/file/wutigibo.pdfIn PDF document text
    • http://mutitar.com/user_img/files/12039420931.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/39834388135.pdfIn PDF document text
    • http://agendaalzheimer.org/files/galeria/files/39300759442.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/78555312855.pdfIn PDF document text
    • http://astmasme.com/userData/board/file/10116470640.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dae4a201a47---91180150617.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac51ea9b129---wolepoxane.pdfIn PDF document text
    • http://kayapaliinsaat.net/file/22313047366.pdfIn PDF document text
    • http://geotersrl.it/file/rorujubo.pdfIn PDF document text
    • http://torgoborud.org/images/file/94287662072.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/brriast67m7k9t14b9jtknqni0/gubaku.pdfIn PDF document text
    • http://mkbeauty.vn/luutru/files/pogutusixasuw.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/jizafesigavivogav.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/e9cacdb3af853d7453bdd00787fe00ff/52648630533.pdfIn PDF document text
    • https://ocw.tw/uploads/files/71847237302.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=cloudstreet+pdf+downloadPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e483.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE483 10616 bytes
SHA-256: 2a89823bfc989f47152a8bb6e802ba492a635a38e0d5acac494a28dae2c98893
font_01_sfnt_off0000fd0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0B 18848 bytes
SHA-256: 6685a223ac4864fa2237f9d33daa4750ccbe2611872c28be49df0405f1d83c1c
font_02_sfnt_off00012dd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1