Malicious PDF — malware analysis report

Static analysis result for SHA-256 b99064527a81886a…

MALICIOUS

PDF

84.5 KB Created: 2021-09-04 07:18:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3ffd0f4fc33343e36bab0b94d621ab93 SHA-1: ab762365edcdb8f67888ae4c7efda4ca6e712d41 SHA-256: b99064527a81886a3da3a9b7ad7ab7b36f1660f7471faeaa21c4c312c6db29dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or redirecting users to malicious content. The presence of external URI heuristics and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://capmar.eu/userfiles/file/52967540087.pdf In PDF document text
    • http://elma1.ru/!upload/files/jikasemewobe.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5692c3b75f---23049307114.pdfIn PDF document text
    • https://alutat.com/data/file/logowosoba.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/f960f862ffadf74a611497c8ff1017d1/2316648496.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/kobukesizenik.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/sefopufamigumigadufoba.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084159c0c58d---zelir.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fba1f7e220---revoxodefelonifaduj.pdfIn PDF document text
    • http://dotacjedlaoze.pl/userfiles/file/beregafuxebilavotubogiket.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbb6a59ff3---25328500793.pdfIn PDF document text
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/i4o2p8kqu0vq4k0pqpvh57u8ie/31814230548.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/1154104031.pdfIn PDF document text
    • http://tjchenxing.com/filespath/files/20210803090055.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/lujezerixamox.pdfIn PDF document text
    • http://avistravel.ro/userfiles/file/jazezijumovejifog.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/43454718438.pdfIn PDF document text
    • http://gimnazjum-krasiczyn.pl/img/userfiles/file/vimadoxafofivuwesuk.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/c6f899b1daf583f21a2817ebc719a138/zowebezuwewosavuxugu.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/xofode.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/4915e3169bce28731301c16d8c4586ad/23085616021.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/93547005496.pdfIn PDF document text
    • https://digireg.dk/upload/3558381327.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/97f5bc90b0399af059562bdeaf644b8c/wejemitibunewifo.pdfIn PDF document text
    • https://harshahometutors.com/uniformkontakt/userfiles/image/files/salimowikalaxawalemobivi.pdfIn PDF document text
    • https://burgaseguros.com/userfiles/file/nizatavete.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=clauses+of+purpose+result+and+concession+exercises+pdfPDF 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://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_off0000e150.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE150 18912 bytes
SHA-256: 8795c950af225b8b9b2e525f3bc781b500b73469af01d9e2fd0d44620fdc282e
font_01_sfnt_off0001122a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1122A 10848 bytes
SHA-256: 07c047b6ff79d0a9ef04f918080e53ff1293f07f78e34770426f61e72c983dbb
font_02_sfnt_off00012b60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1