Malicious PDF — malware analysis report

Static analysis result for SHA-256 66ff3391ece63284…

MALICIOUS

PDF

83.1 KB Created: 2021-07-16 12:48:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: ee8d063a456e5717ecb3afd49a5291b7 SHA-1: cff869ca6a37c4671ecef763e6f6442ea75caabe SHA-256: 66ff3391ece63284e0fd8504a0d17eb12e016f2b9f638992acf5679112061352
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous links pointing to compromised WordPress sites, specifically within the 'formcraft' plugin's upload directory. These links likely serve as a link farm to distribute malicious content or redirect users to phishing sites. ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature. The presence of multiple external URIs and link farm heuristics indicates an attempt to lure users to external, potentially compromised, resources.

Machine Learning

  • Nyx PDF Classifier clean score 0.1247

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6910ea1d3c---binezobunixifonu.pdf In PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbdd1bd0dbc---31128593944.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2800b250e5---fivimimili.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609766903c6fd---xovovewirojovewumezozine.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b8143a2e668---tobubevuxi.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/95358995403.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/efeg6tvnj9s68rf8f5mnamslo2/82574818177.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade9ac9e7f9---simenozoniva.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/xesesadizuwisolewizo.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607782ba3f436---jesalewowuzegopelobisa.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160806ada7625b---7274803822.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8d01f6e048---18226647347.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/dd869gkq26lakqrnlvrva0flt2/kileguvozovibadofazurisid.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d19b03f3b55---7433968239.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/kebemevotatix.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/xobobuk.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/pelfgi475r8iciesn0j32l5bji/86391939421.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/nevitinawusufatujuwewoke.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/a5bh5mi28pu9omvijbjaavshr1/bivuvezopikufiwuxatuzuje.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/lonatatoruxadosuwobamawid.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/jazadusapitojir.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16089fe8521f3d---32064468997.pdfIn PDF document text
    • http://capital96.com/userfiles/file/nevosop.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/ge75b31ehlmp6gvfo9d7qog8cg/7864556323.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607effe6c121d---kamafeneramu.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16072c8d626dba---53140735735.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=what+does+ctrl+a+meanPDF link annotation
    • 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_off0000ef35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF35 17140 bytes
SHA-256: 6f27b8bb7a7c3ba36d6bf99e43d473edd057beeb84eb76d42a9ae3d93444f55e
font_01_sfnt_off00011c23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C23 10536 bytes
SHA-256: d104f7f18582695d0af5e21e3ac44da96687c7e6d1c436a8e8d34f174cc90d5d
font_02_sfnt_off00013402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13402 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1