Malicious PDF — malware analysis report

Static analysis result for SHA-256 a84f29b74eb6380b…

MALICIOUS

PDF

87.1 KB Created: 2021-06-27 03:48:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: efad39764ed720531dc6cfa36e80abaa SHA-1: 059d14986e045ee090a740d1e2645fae04b1c31d SHA-256: a84f29b74eb6380be27c86ee2b2389d2a993bf53be36f18b4b7f50ccc58d9586
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, pointing to multiple compromised websites and disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/gnq52qod91p06siipnm7a4v915/xobezoxujalez.pdf In PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080e4c76a65e---pefofagexajipusojag.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/fativanowilosirogugixe.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/ni97r24lbiecnmbtcrcvfi3525/3223054221.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/baa37oo1rcebrs821f807st4gt/71462104549.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/donubutisuwopobagitu.pdfIn PDF document text
    • http://ibtaker.ps/userfiles/file/63946930371.pdfIn PDF document text
    • http://com123.vn/uploads/file/27923609788.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5fd5e4e09---48070654811.pdfIn PDF document text
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607022822c9d0---wuvubexejokaxiw.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/jmdrn976a5shts6nr5ebh592o2/kudugofobinofapajetoxeve.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/dpjmivue1ihgd003h2jpf7osoh/88326430567.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/e4a7b02dd4d9955b2f7aa82869c7da9d/nizibevasulazego.pdfIn PDF document text
    • http://dnepropress.net/files/file/57726450652.pdfIn PDF document text
    • http://yournamebadges.com/withyourdog/cms_uploads/file/60551892964.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/l13fbcbq602dhgf6ccsgnlovg7/zonij.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/e86dda7a20c32deca5bdef12166d8072/lanadozimowuro.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/e28578b8403e00c0db0f57c6c680b708/92206941285.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/niworafavogadizesawim.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/b7817c596ae6cefd50520a81fb4f4803/jobifizedoro.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160d1ef52aff2a---sajakuvogoxuxejobe.pdfIn PDF document text
    • https://anup.bo/images/files/89788576659.pdfIn PDF document text
    • http://dynamic1984.com/user_file/file/todobiboponadopokukeroko.pdfIn PDF document text
    • https://bursac.net/userfiles/file/gilusolonov.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba889fe8038---11671677692.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/85cplqnk01ac5kcoinh0hdse27/30326951877.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=patent+to+retailPDF 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_off0000f1c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1C9 18048 bytes
SHA-256: 4c9c144c380dbcc5a72f5f86c700a8080b3accb886ca074ec03b7711e6e2456b
font_01_sfnt_off000120e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000138ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138FF 9932 bytes
SHA-256: 2e5788a1f5307184201cc1a23ad6949e709d0506c512856489b2ee352f6d5e18