Malicious PDF — malware analysis report

Static analysis result for SHA-256 528f41662af8742b…

MALICIOUS

PDF

73.7 KB Created: 2021-09-04 22:48:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c5d7791fe8b9b9f89eceacfcb4a43db8 SHA-1: 41865d11cc8018b2aa420d4c6deaf12f2b09b191 SHA-256: 528f41662af8742bbc2c354cba82b49829bf72ebf94b8a0531c65a8cb3c5ac0f
124 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a pattern of using disposable hosting for these links, further supporting a malicious intent.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3852

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 http://banphimchuot.com/userfiles/file/72592329985.pdf In PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/49075511485.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bfe4d3dd20---safiniw.pdfIn PDF document text
    • http://chothuexehochiminh.com/userfiles/file/moxub.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/c37f56bc834712eae18861abe8a613a7/24494529941.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5eb73d2a36---zazepolajijopot.pdfIn PDF document text
    • http://ashioke.com/images/library/File/rowozaxapujubupukogitaw.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/5e22d5c425b22cda7d036e179957ce98/85693035227.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/pnvoht283jr0ra0shkaikqohj6/baxisafexamututigimi.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/benapavuwadevazanapalava.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/mumubiseva.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/geraxidafesujunupanavo.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3fa2a5a1bb---94776359636.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608af88c0339c.pdfIn PDF document text
    • http://www.ddu-hk.cz/ckfinder/userfiles/files/lipanire.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/janek.pdfIn PDF document text
    • https://cavalier-hundezucht.ch/userfiles/file/2453902727.pdfIn PDF document text
    • http://chrislahoda.ca/userfiles/file/97610524722.pdfIn PDF document text
    • http://medtravel.pro/images/hand_uploaded/files/buzejipuf.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160ce891e581ac---11700792504.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982c4219611---30630482204.pdfIn PDF document text
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210620001547.pdfIn PDF document text
    • https://digireg.org/upload/66992936024.pdfIn PDF document text
    • http://hmconcretemixingplant.ru/d/files/8450666736.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094bfa319f2d---vekekorumiwosekavero.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=printable+body+measurement+chart+pdfPDF link annotation
    • 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_off0000e425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE425 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC37 15736 bytes
SHA-256: 499eee18a17b626f65dd4842bdd4be4844030841be951fc85d287d21c0ba3796