Malicious PDF — malware analysis report

Static analysis result for SHA-256 cac1da34345319f5…

MALICIOUS

PDF

83.9 KB Created: 2021-09-13 22:25:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3933c47451bb9fca51cfcb59cd388c1b SHA-1: 6b751be4399ae24c5b6be5c831700e87b24e7148 SHA-256: cac1da34345319f529a9800ca03dad8599f27432bf4e6816ba7cdfb3d6c70dbb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URLs, many of which are hosted on disposable domains, suggesting a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly supports this, indicating the document's purpose is to distribute links. No scripts were extracted, but the overall structure and URL distribution point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://medvor.ru/uplcv?utm_term=how+to+know+if+someone+has+searched+you+on+instagram PDF link annotation
    • https://safrano.pl/userfiles/file/pufesepibenirudi.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/gudolatosenesirufuma.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/87986029029.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/7241875336.pdfIn PDF document text
    • https://12shio4.com/contents/files/49536428422.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/fegejufudewexulijodadotak.pdfIn PDF document text
    • http://a2kat.ru/userfiles/file/dudiketemudaselud.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/lumoris.pdfIn PDF document text
    • http://potya.com/lotibulilokajumonanike.pdfIn PDF document text
    • http://www.jobibon.com/admin/userfiles/file/70068824022.pdfIn PDF document text
    • https://artenika.pl/fck/file/buwuzosos.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/47445160981.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/29157475980.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/rimalamolox.pdfIn PDF document text
    • http://childconnect.com/swi/fckfiles/file/29634207721.pdfIn PDF document text
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/60248698398.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/xukek.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/fisenabunuzezevomeseja.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/96476291773.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/loxikozevovajijewafujeze.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/kamolosafezowediwokiwuzot.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16134bccf34fc6---zepupuluranusilolarete.pdfIn PDF document text
    • https://nevjegyzek.eu/uploads/file/19585812356.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/62305e77d1113988e3b2debb4f79c49d/negubevakepagokubadibuk.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_off0000dff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f80a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80A 18316 bytes
SHA-256: b288f9aad6781ea01da132a622c34835159d7726f0ce0c47cecceb61ae7553ed
font_02_sfnt_off0001274c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1274C 11260 bytes
SHA-256: 8d607a61b691a042a9ee2e9862f8f7b2bf54d0dfeb937c1ed7a7136530dc82d3