Malicious PDF — malware analysis report

Static analysis result for SHA-256 35fb0c1556963e0e…

MALICIOUS

PDF

72.9 KB Created: 2021-06-21 08:22:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 2efbe374031c3c428144dd18edd709bb SHA-1: 2a4940766ef756dcc4c3977e98ff49f3cccad58a SHA-256: 35fb0c1556963e0ea8f6ebcfa5caa199ae5b06d28a62605737a06707f99bda6e
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating an attempt to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, as these rules are designed to identify phishing and malware distribution schemes.

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16075a81bc0934---31536072212.pdf In PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/if3ul0jciaeirfhsoo9encf9ca/43602988634.pdfIn PDF document text
    • http://vorne-sitzen.eu/pcms/content/file/19161649343.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fabb32f312---68126065862.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/fd9041fe633392d92d39d45f7db6ef97/18646716503.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608aded9c4250---puzosenopo.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/30660376060.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16072135b1c9a2---ditijem.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/f98489707738a4da245a535342e6799c/21001424518.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/bobexoxutovafetobifab.pdfIn PDF document text
    • http://border-inn.com/CKEdit/upload/files/fiwapebepatu.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/e2544c224137cec8de95341f4b379c82/53854235487.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/559dfb94ba023c55ba412efd0b0dd96b/86167874465.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/wudoza.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/e039949dbe14a7b9543c324d678c29b2/88937206030.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/15b118e4bb2c26362dd8a10050a21217/dupixizuwijajufewolegovi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=insta+followers+pro+mod+apk+unlimited+coinsPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE2 5392 bytes
SHA-256: 479dc5c965a04ff66559353ae57dbe0baa46100f3993aa525d6370701b8ac598
font_01_sfnt_off0000f139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF139 11392 bytes
SHA-256: ece7e95972521babaea3d51b0ac3ad3a4d2f75fa559875eb2e2763a847f7235f