Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1fc5188bd796869…

MALICIOUS

PDF

91.8 KB Created: 2021-06-09 19:32:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 79e611646763be4ed3288b3edab16674 SHA-1: 51b2ff608dfa81a106df5aeafe97547fd3680aab SHA-256: a1fc5188bd7968693d00fbbb81835226b26198bc8ac4b097122e9b7be13aec4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many of which appear to be hosted on compromised WordPress sites, suggesting a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, indicating it was likely generated programmatically to serve as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crysiq.ru/uplcv?utm_term=batman+begins+script+pdf PDF link annotation
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6ab06e14d---86546289714.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081fea7b847d---nujuxonubosa.pdfIn PDF document text
    • http://allasclub.com/campannas/file/42717249407.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210510030307015.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/salumuxegavawe.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c22d3fc46---kesakivo.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/21ba17893c0d4397fb36f49dbcb3ef69/wibasixano.pdfIn PDF document text
    • https://www.propertyadvisersaustralia.com/wp-content/plugins/super-forms/uploads/php/files/37a972a3e28dfe290daff399b511be0c/bagopepa.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acc99a0e38d---fewedotawezap.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094cb1811796---81523247197.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/uleo5dmf86ks87hskgqnhki9kg/tejudir.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/c3af9f3ab64dd7266e7003fbad202d1a/zerezano.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/fmq20tbvqiqf3ab4fe6g5hlmbv/vexisufim.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16070f329ac470---vipesupurekal.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ee3db2fa3e---xibusinesomor.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000128cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128CF 5632 bytes
SHA-256: a923642497e34a12531081fbfe1e2720c1227156963fa61a687ecab2c9a4b48c
font_01_sfnt_off00013bde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BDE 11396 bytes
SHA-256: 86184e665d4f7671b60bf0a31535375f12d800a871b92783182e19e0f64169d1