Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a909c9c90c40113…

MALICIOUS

PDF

80.6 KB Created: 2021-09-12 15:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3d337eb7a38bdd0d39b84fc47015d713 SHA-1: 4643ee1660ca0f393ef3216204b8d97fd16d043e SHA-256: 3a909c9c90c4011354f21a1d6c5c36fc419fc87a5f05b941390f20a51c8e1582
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating numerous links on low-reputation hosts, often with UTM parameters, to manipulate search engine rankings and lure victims. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • 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://ytovietnam.net/ckfinder/userfiles/files/levalaxajefo.pdf In PDF document text
    • https://behbehaniprojects.com/uploads/files/30326752179.pdfIn PDF document text
    • http://taeguektour.com/FileData/ckfinder/files/20210904_5821D66DB8A92876.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/ludux.pdfIn PDF document text
    • https://umiyawoodworks.com/fckdb/userfiles/file/28162972084.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/reputavidokegimusapaxa.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/gexebum.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/iio0hgvhkdgaod2di8dimvsui3/budetugabi.pdfIn PDF document text
    • https://congtydaihai.com/upload/files/malosunorefajazimadib.pdfIn PDF document text
    • http://cokhivietuc.webthoidai.com/img-vietuc/files/57459642378.pdfIn PDF document text
    • https://a-1commercialkitchenservices.com/ckfinder/userfiles/files/70133280486.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1efc85d3c---dopodizogazemaliziz.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210902140906.pdfIn PDF document text
    • http://baominhlabors.com/upload/files/beviwe.pdfIn PDF document text
    • http://freeski.hu/freeski/file/59156474801.pdfIn PDF document text
    • http://bridgeonlaw.com/filespath/files/20210908123715.pdfIn PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/sanovodarabi.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/fotikanij.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/zulub.pdfIn PDF document text
    • http://orenprom.com/img/account/file/zitazubakuxure.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/44742230405.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/25182307006.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/pevutixegelap.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133657bc1bb4---mubimipug.pdfIn PDF document text
    • http://luxlustry.ru/img/upload/1671761419.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=car+game+parking+download+apkPDF 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_off0000d436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD436 18528 bytes
SHA-256: 8891574032af8a4d38d32261e797d303969db8982daf9191bb7514d740927f3f
font_01_sfnt_off00010470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10470 10680 bytes
SHA-256: 45b685861842f8a0bbb18ffba7addf795595c4073b3999e58d95695947540f2b
font_02_sfnt_off00011cb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1