Malicious PDF — malware analysis report

Static analysis result for SHA-256 258d55783abdc643…

MALICIOUS

PDF

156.9 KB Created: 2021-08-02 04:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 817bc27396ddd1b8f357361a9499e59a SHA-1: fc44d7c89c92574d0c14d3c51d001aeb8e32d254 SHA-256: 258d55783abdc643be8972c2cb02bbd6578a459c8b5dc7d4bb77a01fcc19580b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating it is likely a phishing or trojan distribution attempt. The file contains numerous links to external resources, many hosted on compromised WordPress sites, suggesting it functions as a link farm to redirect users to malicious content. No scripts were extracted, but the presence of external links and the overall structure point towards a phishing or downloader attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7037

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
  • 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
  • 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://cructi.ru/uplcv?utm_term=magnification+and+actual+size+worksheet PDF link annotation
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/7ea8ab72e801024f66683eac0c2ea16b/bosibifaragetamefurije.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/dupaxinerun.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16072ce79cd735---93295402440.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/31020916599.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/fn732tdjt6mthlcc48qtt7bo92/72172609581.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9abf02b0a---31901247645.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/12498483577.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/vrfln7oipp27rh7jh3rd330em1/jemeboduwaxuma.pdfIn PDF document text
    • http://eurolocal.info/sites/default/files/images/file/rewab.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16075df6f64e83---95762753455.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/jotadelibolupuvewo.pdfIn PDF document text
    • https://dodatnagarancija.com/userfiles/file/jekamo.pdfIn PDF document text
    • https://beauty-full.ru/uploads/files/74522402130.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/65215151993.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/jujizamemegumo.pdfIn PDF document text
    • http://chiengthai.com/file_media/file_image/file/10575554794.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/kilinifinezixuxoz.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1622575411.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/26263787883.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082a6738792a---7103010080.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc438561a8---87782315417.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/5ca481a16a7a573d1dbd33c7407b534f/7265364815.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/85c6d8a511331f8e36deaf5527bcb74f/9990911483.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/bumufejojokademob.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00022455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22455 19344 bytes
SHA-256: ce389684f680f7c4efe2ecda31d83214ab3d9b74d7f0192dffba52e772b9c6fc
font_01_sfnt_off00025648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25648 11084 bytes
SHA-256: f733855b82eaa807e676d90346e67e7e7bc0be8ee62a7fca1ccc6ec5a1dcaa94