Malicious PDF — malware analysis report

Static analysis result for SHA-256 844f6dd3342081a3…

MALICIOUS

PDF

84.5 KB Created: 2021-09-11 11:54:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 064b6f057bbfe93857723d69429fc533 SHA-1: 2667f49936ebc089da2b4135ff871d068d73c40b SHA-256: 844f6dd3342081a3823f665afad22fc8ff1d4f4f1d4faf003f06561c135bc126
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are hosted on disposable domains, indicating a link farm designed to obscure the final malicious destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bac1b6370c---tatazozeworapuxavi.pdf In PDF document text
    • http://theffirm.com/userfiles/file/podaro.pdfIn PDF document text
    • http://caphegiabao.com/upload/fck/file/95467998001.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/80997990591.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/44403310894.pdfIn PDF document text
    • http://delve-cr.com/uploads/72994414569.pdfIn PDF document text
    • http://cnex.cc/images/blog/file/napupirofonifa.pdfIn PDF document text
    • http://blgjad.com/upload/files/petexaguvajubewafiritexo.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/85418756497.pdfIn PDF document text
    • https://kidneystonetreatment.in/userfiles/files/rekag.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/73325048718.pdfIn PDF document text
    • http://jca-t.com/fck_image/file/82713456618.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/wotezawavanopilawaro.pdfIn PDF document text
    • https://bonvoyageindia.in/ckfinder/userfiles/files/masenekurujafadubi.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/kemavafovefaten.pdfIn PDF document text
    • http://as-eng.biz/userfiles/file/tamamabowebufelad.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/basutajufizamoguzep.pdfIn PDF document text
    • http://freeski.hu/freeski/file/pixigegitorutixazujud.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/degofaturezesalib.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/62925138240.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be11f4daed---fapewuvawukepi.pdfIn PDF document text
    • http://proficlim.ru/public/userfiles/file/savikajobuku.pdfIn PDF document text
    • https://mimpidia.com/contents/files/tozan.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/rizawirodamepagopam.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/watazar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=free+robux+no+human+verification+and+no+offersPDF 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_off0000e396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE396 11080 bytes
SHA-256: 53a16869f5428ebaf615fd5a1e7c7ed4277063b4498cb10f6bca9fa0e19c939a
font_01_sfnt_off0000fd42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD42 17860 bytes
SHA-256: 9e27f6f43c3cda78b6adad2d74699fb908ec9c39608d82020881ca0e554c7662
font_02_sfnt_off00012c18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1