Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3b31ff58dd86ff4…

MALICIOUS

PDF

79.6 KB Created: 2021-09-01 09:46:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4372f17e73ed39266bfd427e193c7f01 SHA-1: d7ce64519543df4d3e966596ac675261e445e149 SHA-256: f3b31ff58dd86ff4d03e8a83d0e8355061f61ae4a95a05a1393b86557b38f1ca
154 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to host or redirect to malicious content. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the true destination and potentially engage in phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8700

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://hohsingfiber.com/ufiles/files/52561614024.pdf In PDF document text
    • http://coinmarketsuite.com/ckfinder/userfiles/files/31260362693.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b944e6f20eb---81410709149.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/f2accaae0624910836374fd600ff3528/pefosok.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/noth8nstgfg9cipbcjq2aghekh/safutupijufojotudizuwubi.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608493a32d79c---letinodilepi.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/dudobavizubegegugemivev.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/1kr284dfos89e90v6ub5ca29b7/96287363083.pdfIn PDF document text
    • http://cmi.nfe.go.th/ckfinder/userfiles/files/xapalefeneranar.pdfIn PDF document text
    • http://xn--m1age8bh.xn--p1ai/files/file/ravaji.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/e5ae6f3c4594a7745944a01ffd755aa6/24289835982.pdfIn PDF document text
    • https://charqueadaboavista.com.br/wp-content/plugins/super-forms/uploads/php/files/4f77eb8edaf3640879b5063ad850c175/zijawelujevar.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/69906856433.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c3ac7411c---42790433815.pdfIn PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30594487788.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a64a09758d0---zejuwoxexibonos.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/69738851106.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/55efef9e5c1146a5abdbe290b540f652/9817843442.pdfIn PDF document text
    • http://brlairport.com/images/file/65671348631.pdfIn PDF document text
    • http://mousike.it/img_ins/files/1777162960.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-23/20210523135450490131.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/61265a02b2213dce9d9518059b5a89c1/riponagubax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=without+a+crystal+ball+llcPDF 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_off0000e8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CA 17232 bytes
SHA-256: 484a768e5d86da12dbfea0b4d79dea5d3f815caf585d943b70e1f21b11199fc3