Malicious PDF — malware analysis report

Static analysis result for SHA-256 41cf6b16a1b40e83…

MALICIOUS

PDF

77.0 KB Created: 2021-05-03 13:51:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-28
MD5: 3395d5e989732b30a843f99795a47377 SHA-1: 24df85defc4b8b55f8ce4fc48a16b6b6947e5a4c SHA-256: 41cf6b16a1b40e83d03bceff387c285f0d85affc9595f6ddaa7c4633a64f6642
164 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress upload directories, suggesting an attempt to host and distribute malicious files. The presence of a 'download button' heuristic further supports the lure-based attack pattern. ClamAV detection and ML classification confirm the malicious nature of the file, likely a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d2b18d40d---75360179028.pdf In PDF document text
    • http://alexanderkanevskyartistbiography.com/clientMedia/file/koluvitanogunometirepubu.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/tavadidaduk.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607cae941281d---xuxejixow.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080ba3f7e234---46632080525.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d944c87cb3---56977268423.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16088e38523cdc---teginiveto.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cba5b22356---sodafitudejesevi.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/77645483971.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/0ba3b7a96200469844095165add49fed/pakagojizegofe.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9e8651592---vovofuzefetufifep.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/269d9aeb01aaf30adf778e45674be3ef/81246351512.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=lagu+gratis+hanya+rindu+andmeshPDF link annotation
    • 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://scripts.sil.org/OFLIn 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_off0000dbfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFC 5252 bytes
SHA-256: f35be6b10bc398c462ecbf6865566156487d91e4edeec9d0a97d09a777c8bac8
font_01_sfnt_off0000edb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB6 10368 bytes
SHA-256: 24b5b108f18a161c76ce1045cdea153b99bd69a07fa253dcfca89685a2c98a34
font_02_sfnt_off0001116d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1116D 16396 bytes
SHA-256: 4e74c91031341c06b915725d15f052d77c33d75b7b3102a675f469d94d5ad539