Malicious PDF — malware analysis report

Static analysis result for SHA-256 13dab8f10cc535a2…

MALICIOUS

PDF

96.7 KB Created: 2021-07-06 06:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 1ede737fa0e91f9bfabbedea5c28fdb0 SHA-1: 8a5ec201de677bf87009ad8ec709ffef2a779fc0 SHA-256: 13dab8f10cc535a237362c7da1600eb63cd0f8c2b1c100bd2c493d64244295d6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://ketchas.ru/uplcv?utm_term=how+to+blackout+in+pdf PDF link annotation
    • http://www.bash.cl/media/file/zurumuza.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607c63295f7fd---gugamakagipudub.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b75599bce---tefufegew.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/nusilusogifepafes.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/018fd7545479b8e5d21294b2271de218/74583640453.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/66661697615.pdfIn PDF document text
    • http://gapoom.com/upload/fckeditor/file/kobapewitekujevebi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071d7176b356---katamipetefefabimi.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/t8osqunkcbuv149ftbhiq1kbk1/94082039051.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/vg7gftb6213ka8k8b4cthtv8dk/kopamaso.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/39155586165.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/nem2h04j53hc2b0nmjg1vqge1n/xapafitebeniveropebafeneb.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a90002ea7d9---mefasudifulokevija.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160dfd322118e4---9738195493.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/28148ddd01ab4a7859486fdcb7405276/tupanadoxom.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607851d2379fc---jemakovibag.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16077892c379ef---75938427034.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/wujoxemet.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/47cad14f06dd88131c6988484e56c702/3713218572.pdfIn PDF document text
    • http://americansemitruckparts.com/d/files/mudexuzab.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/4927bab2904d931640d7e0b8d7add30c/fibalara.pdfIn PDF document text
    • https://mollis.rs//files/99223594668.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/0792cad58168ffc82d08f50d596f3de7/jovamunu.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/91193971755.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/milebixolik.pdfIn PDF document text
    • https://mimpiindah1.com/contents//files/woviwajupupizuke.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_off00011612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11612 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012e24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E24 17860 bytes
SHA-256: 1424756a5e9d344c5dd5566e90307d09fa05ff076ac3d45c25b2aa806ceb4544
font_02_sfnt_off00015d93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D93 10620 bytes
SHA-256: df3b188b52bdd85264c419b95aa80d7e0862d437f827f5af1bbc9a0cb136daaa