Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe8942749a983e1c…

MALICIOUS

PDF

78.6 KB Created: 2021-09-13 10:06:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 591ad211ba1caf58ac12f9884bd9777b SHA-1: af02d66ca3b26d407a9c583fdc8e5f66ff4c5094 SHA-256: fe8942749a983e1cb75f75d96ef1a0447c0438775c1aa58a4bd2a69eba5a10df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs that function as a link farm, directing users to potentially malicious websites. Heuristics indicate these links are often hosted on disposable or compromised domains, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://synerhu.ru/uplcv?utm_term=free+app+for+watching+web+series PDF link annotation
    • http://www.pzkexie.com/up_files/file/pivesukirizusojenakufuxa.pdfIn PDF document text
    • http://goref.ru/files/file/74340615603.pdfIn PDF document text
    • http://beverly.kopanramen.com/uploads/files/ririnob.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/36370634185.pdfIn PDF document text
    • https://stoneappeal.in/FCKeditor/file/duduwewewim.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16139182bd04ef---21184065546.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/80899595134.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/gosemavakelufi.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/39373351967.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109021556272709.pdfIn PDF document text
    • http://orenprom.com/img/account/file/lepuxuzegexiwotiko.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/57914094912.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613544a3450f0---xoxedekigisote.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/64777884400.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/59428969472.pdfIn PDF document text
    • http://ukrkarta.ua/fckeditor/userfiles/file/laroje.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/fapatavaputapikabipe.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/noxigarivuri.pdfIn PDF document text
    • http://spec-so.ru/sites/default/files/file/ratopunorozatezojubi.pdfIn PDF document text
    • https://southwestlooms.com/admin/userfiles/files/nejuleviz.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/dawewiwovikino.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/pogusazowo.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131202134e62---91209607862.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/44876649233.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_off0000cf2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2D 17160 bytes
SHA-256: f5c7f5b088d81bebad3ef6db4f75f4875a4256f4146ed68e1a92b789498a05b3
font_01_sfnt_off0000fbbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113D6 10916 bytes
SHA-256: 8f4282940c5e7d1a5636e164875b5d0f614711874ec5359b0c3d55fe63924eeb