Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f9194eaabf3af9…

MALICIOUS

PDF

138.8 KB Created: 2021-09-20 20:44:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fd9a9bfdc159241a03a59b01032b40b9 SHA-1: 909b89b8d6906b83c307d4359b27fc743a368273 SHA-256: 81f9194eaabf3af9110abf022550950bf80ff9eb20df10dc924ac81a848f574d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, suggesting it is part of a link farm designed to redirect users to malicious content. The heuristic 'SE_ENABLE_LURE' indicates the document likely instructs the user to enable macros or editing, a common tactic for malware droppers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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://catamma.ru/uplcv?utm_term=naruto+shippuden+ultimate+ninja+storm+4+road+to+boruto+ppsspp+download+highly+compressed PDF link annotation
    • https://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/95345557973.pdfIn PDF document text
    • https://www.vignolaweb.it/ckfinder/userfiles/files/47921815059.pdfIn PDF document text
    • https://haciendaloscipreses.cl/upload/file/63667918613.pdfIn PDF document text
    • http://kalkulacka-hypo.cz/userfiles/files/46919174027.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/mamidamudimelij.pdfIn PDF document text
    • http://jiji.pgo.tw/pic/uploads/files/nenibopotobolozo.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202197_55854_863.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/pobewunalawejuzabamolikim.pdfIn PDF document text
    • https://bostaninsaat.com/image/files/92261780345.pdfIn PDF document text
    • https://makenie.com/upload/files/70438541013.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/51860972954.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/lameditepuvafizifo.pdfIn PDF document text
    • http://magicfood-cn.com/files/20210915230933.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/161381e05c77fd---41180173101.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/jopegunor.pdfIn PDF document text
    • http://oris-am.com/editor_up/vudupufixutiziv.pdfIn PDF document text
    • http://houselandia.ru/files/dajubatale.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/file/rukumazij.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210910190856.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/pabofawixonemasuw.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/37481342647.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/9528737994.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/32185918148.pdfIn PDF document text
    • http://caycanhtuyhien.com/uploads/image/files/73162883561.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///kugemanijenedugofedexeja.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/95406067767.pdfIn PDF document text
    • https://dm288.rs/slicice/file/86504640309.pdfIn PDF document text
    • 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_off0001b43e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B43E 11588 bytes
SHA-256: 5ba9596d498a0ad384895ab61186f4e2f06032d7bf7ad6930081c71245608059
font_01_sfnt_off0001cf41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CF41 18796 bytes
SHA-256: b7750074ae162fb5ed5aa0f7e5422d06f35b1547953d0dff26de4cde253ae00b
font_02_sfnt_off00020148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20148 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1