Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3cd75208556d7c8…

MALICIOUS

PDF

69.8 KB Created: 2021-09-25 07:53:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4df6548f4bfdcc2e3f1cb4169d88e682 SHA-1: 0d8ce7e80eba3192cbf99a2d0685323253364b4f SHA-256: a3cd75208556d7c83f4171981eb9f91e791c2575e5c585c29633113a01aa05da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics further supports the attack pattern of luring users to external, potentially harmful, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://nomylo.ru/uplcv?utm_term=android+screen+resolutions PDF link annotation
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c838466f29---sifanuwux.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abd3a0779b---fibabuvotol.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/tnar7jl95jv6hjj02deogbf09d/sekukawivoxawopevasegilux.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/data/editor/file/20903517167.pdfIn PDF document text
    • http://apcmagon.com/userfiles/vuxoxide.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/lenedosifejujura.pdfIn PDF document text
    • http://bosch-elektronarzedzia.pl/catalog/file/seridobevodefipo.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614674b5d90f5---21439798606.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/69727545928.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/bowodewizimoposewolexizi.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/hlmndtkii5pjdlid7vslki8vu6/86672300740.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/95875906184.pdfIn PDF document text
    • https://bursac.net/userfiles/file/kibidejuvolezesap.pdfIn PDF document text
    • https://silverstonedevelopments.com/ckfinder/userfiles/files/zirewipoxuvavilelus.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/kunisavosibinik.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/62208865996.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/72795167529.pdfIn PDF document text
    • https://superpart.com/files/mogimajarazuka.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/57543265625.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/83498027478.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/o6qv94k0r4vhph8ap5saejdeq7/69259523176.pdfIn 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://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_off0000b15e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB15E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC975 10284 bytes
SHA-256: 3fb9a76f7fe3c381f72e89e42add4bc3509d39018f61aeda433764e5f65e52ad
font_02_sfnt_off0000e0ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BA 16212 bytes
SHA-256: d54bee1d2c21a2c86e3266a23b73b841f7d25d83efa37e421d7e3ec95c5ad4f3