Malicious PDF — malware analysis report

Static analysis result for SHA-256 af054da07f05c163…

MALICIOUS

PDF

75.7 KB Created: 2021-09-04 14:11:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b0ef320ccad4ccf217814e401915dcde SHA-1: 55bddab46aea7e231cc415e67f9e87b16ff12a79 SHA-256: af054da07f05c163728470540409884d9c398ca71bb761585d6b1021d0ebc559
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan distribution vehicle. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on compromised websites, likely to obscure the ultimate malicious destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests a tactic to distribute malicious content through SEO poisoning on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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://chothuexeninhbinh.net/data/dulieu/files/wobepe.pdf In PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d351054e68---vowarinaxuvopizene.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098189f51cbc---37172560971.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/c875f405f6b5aff829db569fad60c214/29740790973.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/xugufesutizademixaxo.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/zozotetoreleto.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/7ac3905a9a1e3bfe080be9e97800c810/14209297684.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/wopurakegetekasej.pdfIn PDF document text
    • https://razredna-nastava.net/files/jefofexi.pdfIn PDF document text
    • https://catbasailing.com/upload/fck/file/makesulinugoze.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fffafd2ba3---rakej.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/fe766c836a69868bd15c9bc43e7f5344/32521808456.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d00de27c040---14956031975.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160a212230ad2b---zesikimivefitolida.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/zokoxavizoz.pdfIn PDF document text
    • http://vitrine-prof.com/files/40543532923.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161144f91b1a24---belijasixadisixagojiz.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/89024955799.pdfIn PDF document text
    • https://northcoteplaza.com/userfiles/file/98967594492.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608a09be57c88---25229949100.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081088110266---wavunekazozon.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/k68q53jr2tp2pqe1030780m0ea/patasaperoponisuxum.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a33a4af789---lovikovaremuloxozok.pdfIn PDF document text
    • http://bmhs1963.com/clients/7/72/7286fd37811b7a5dece6e69924e4d5ab/File/71297606876.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/poravetabazunedilab.pdfIn PDF document text
    • https://glory-aqua.com/userfiles/file/13757004920.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=comparative+literature+a+critical+introduction+pdfPDF 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_off0000c197.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC197 10812 bytes
SHA-256: 082e8f03cf00c392c2c8d76df6eb4d0d363ed2ae3491909773a3346da6ef6499
font_01_sfnt_off0000da87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF299 17680 bytes
SHA-256: c49c8190da7c6867cccd64e994bf3b5f16b0acae5df6ceaf0eca14ceb676922c