Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a565317ef95b100…

MALICIOUS

PDF

87.5 KB Created: 2021-07-16 13:46:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 25750e4b80b7004b917ff4ada7b9c7e2 SHA-1: 4e6df140e058eee3e497687133252cabc86db3bb SHA-256: 9a565317ef95b100dae6c5320f91150c16ed2643d87aa176b756970bd7537f25
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external links. Several heuristics indicate that these links form a link farm pointing to compromised WordPress upload directories, suggesting an attempt to redirect users to malicious content. The embedded JavaScript likely facilitates this redirection or further exploitation. ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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.
  • 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 http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c878a75476e---74205083859.pdf
    • http://alphanaturehk.com/userfiles/file/gugamusezuxoxawekenaxa.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/0c1tqdrpk65rfp61hrva1b6id7/95975325088.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f03a0f63d---nadij.pdf
    • http://anaminfo.com/attachfile/file/29536746596.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/5dmlhacnutab89q2sjcfjiisr7/wazovi.pdf
    • https://arket.io/wp-content/plugins/super-forms/uploads/php/files/o76u4e5e7j1tkif2klco2hp6vo/2715775840.pdf
    • http://murasakijr.com/uploads/files/zijopebigivajorofitej.pdf
    • https://parklanehotel.asia/userfiles/file/selunokaso.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160beced944761---nukebowiximokupoges.pdf
    • https://chachachat.info/js/ckfinder/userfiles/files/97180077110.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/2dc78fcc6953014ca148049fcb73234b/muvawegusiniki.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/c214046pk726ormg46dlmm9b9e/mewusasomujur.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d0016705155---jokuzejer.pdf
    • https://majorsagilekvaros.hu/uploads/file/lofumovavaxomakazoxifok.pdf
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16095e6542108a---32802060502.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/d8e1648a30cf5f0bcb3c44730cee28af/93270433670.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/5fabbc8101f0eae976e9ecbd794db895/busexujar.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fc5c817d14---34125686166.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/mc8r1lrpnefp68mm832a4flpt3/lumunujuratomuxokonep.pdf
    • https://jahanchart.ir/data/files/file/zowoluxefinetedogaxiferor.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f30e614a5---sudido.pdf
    • https://sanaspinler.com/calisma2/files/uploads/91931220967.pdf
    • https://briljant-maleri.se/UserFiles/files/71142979907.pdf
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/11154100704.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a165ae598f1---kulitujixubowenavixilewex.pdf
    • https://acronimocostanzo.com/userfiles/file/xanurujuwemedoxuzaxugije.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=download+song+count+on+me+female+version
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f23d.bin
639360f679a175b8431bfd53e17a7b30880a36a03ecab4f8c349e13c6a6e2247
pdf-font-stream PDF embedded font (sfnt) at offset 0xF23D 11072 bytes
font_01_sfnt_off00010be6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE6 16792 bytes
font_02_sfnt_off000123f8.bin
cf98e1e131bd0700ff0fca8f92ec177bd5cfb8c549768e7415e7c79e1b27bdac
pdf-font-stream PDF embedded font (sfnt) at offset 0x123F8 16936 bytes