Malicious PDF — malware analysis report

Static analysis result for SHA-256 a78e878a93d372b4…

MALICIOUS

PDF

84.9 KB Created: 2021-06-25 15:44:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d40c85a5109ddea43c5082bd4a077f68 SHA-1: fafed3196f05837eb42e93e8d30db45761412112 SHA-256: a78e878a93d372b451e284e2db5b8c8229b0a1895d249397f6eb3b2043c2ef7c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ML classifiers and ClamAV. It functions as a link farm, presenting numerous URLs that point to potentially compromised WordPress upload directories or disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear textual lures but the presence of multiple links suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://teraval.cz/res/file/gosusojanerovimok.pdf In PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16094b4c923475---vobozafenirewir.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/9d152391552a3ea57bb084acc033417c/20609484883.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985bbbc4688---62641086920.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093a514a1507---jibuzuvewawa.pdfIn PDF document text
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/a7b4e3166f19379beb7bea001146da55/lawesalusovoke.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/tetexagasesuj.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/8511957877.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1607640286c4e5---silowimerifoxojafemaf.pdfIn PDF document text
    • http://bdn10.cz/files/file/23644235020.pdfIn PDF document text
    • http://msamerica.net/clients/873634/File/zalotagilogiva.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ef27c0562---kasirowakatepar.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/4513256285bb1ebb2a0cd26ecaf5d527/jibaxiviragezevenafa.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160794f27c6e26---58733798348.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=the+amberly+apartmentsPDF 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_off0000eb78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB78 10520 bytes
SHA-256: 0d19cf800c8f71b337f6f5164aeda0c63b5e39bee13286953029e1c5300bc3b3
font_01_sfnt_off00010305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10305 17036 bytes
SHA-256: 7c3deb998b53f2c105ed714d02e0c36a525da71e9084e9b93b4e40a2f816c597
font_02_sfnt_off00012f76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1