Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef55e8f9699ac9ff…

MALICIOUS

PDF

79.6 KB Created: 2021-05-31 08:52:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: ffdadd36eed0b87b563052cddf536b2a SHA-1: 277fdafba6208c3af382682c39e45a823ac2fe69 SHA-256: ef55e8f9699ac9ff79e3575727e6e9d3523baa57efa5ee0bd2377ff34aed901b
156 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to multiple compromised websites, likely intended to trick users into downloading malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, with the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supporting the phishing lure. No scripts were extracted, but the overall structure suggests a phishing attack.

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 http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608c293c8b94d---15355792659.pdf In PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/d712abb911699c89945e07b7dbe68f96/17758162178.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607adc9615060---jotupikovefakumizan.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1607035017f04c---90898919327.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160765a4b0bf87---52479488574.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093697a6c805---2138424224.pdfIn PDF document text
    • http://asfalon.com/__files/file/teteriripisuli.pdfIn PDF document text
    • https://www.alapan.org/fckimages/file/74382800387.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/ct90rt2omik6i3fstosriklqs6/difafon.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdff83ee9e---lifokekaputelenajeligo.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16072339fa39f6---dirilofel.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/a2de02e8d906af2309ef7d897ea4da1a/27142790381.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/c0812ddf273709e437da8c5b61aa89cb/fitesovokuzuramutu.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/femalafezikugujaxipapa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=caderno+de+caligrafia+artistica+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE942 5132 bytes
SHA-256: 3d88b31a848a4e7b41272d8cbac2805c5a7f25bc8f2d0d5a4e6b351299193aa8
font_01_sfnt_off0000fac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC4 12812 bytes
SHA-256: 561899f835ce50a54f03523d84c6bf9a480804a68ebd483342cd437ae8ee6acc
font_02_sfnt_off00012144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12144 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34