Malicious PDF — malware analysis report

Static analysis result for SHA-256 551532f7afdaa77a…

MALICIOUS

PDF

76.7 KB Created: 2021-09-09 23:08:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6e5d04da1d784839e15b1b946999d94b SHA-1: de5ae398a40846a3a5bbcf393837cd48d68f5d11 SHA-256: 551532f7afdaa77aefb24e8d2603163ef62b9331e299a9b2207ea39dff0dded6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://stlukesfp.org/ckfinder/userfiles/files/48387279582.pdf In PDF document text
    • http://auto-spec.ca/fck/file/95727145702.pdfIn PDF document text
    • http://biurod9.pl/public/userfiles/file/bikideve.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/batuni.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/75324822716.pdfIn PDF document text
    • http://soepcentrale-dekeyser.be/userfiles/file/fulufegizatamagosexox.pdfIn PDF document text
    • http://thebodyclubonline.com/userfiles/file/dawikagipefowaje.pdfIn PDF document text
    • http://dymenahealthcare.com/upload/fckeditor/file/pozofizegafizilowetevos.pdfIn PDF document text
    • https://uleshuzataruhaz.hu/files/file/69201847124.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/i73ol1orq0o3imdt4fa4cou3id/26695924282.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1613040390141e---68483071654.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/pejinatosefapipax.pdfIn PDF document text
    • http://roocenter.ru/upload/file/vimimegebu.pdfIn PDF document text
    • http://aminotp.com/upload/files/50272220017.pdfIn PDF document text
    • http://dienmaythanglong.org/uploads/files/34419908554.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109052146209184.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/polijab.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3d28b414e---29057594389.pdfIn PDF document text
    • http://dalaichau.com/files/94267670333.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=redmi+note+10+ram+and+romPDF 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_off0000c0ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0EA 10416 bytes
SHA-256: 7593d781c72182dc66be7055418fffe02ee653f9258640c82400d56fa27746cc
font_01_sfnt_off0000d87c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87C 19928 bytes
SHA-256: ae09e7789b5096dc1d838877e8c7e19c7f1322f37fbb7977c768e4e6c320c53e
font_02_sfnt_off00010d51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1