Malicious PDF — malware analysis report

Static analysis result for SHA-256 3148ac1190c9417d…

MALICIOUS

PDF

71.6 KB Created: 2021-05-27 14:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 0d83c8bfc3611fa8e50d90d45378df92 SHA-1: bd7374ceca90f3df6aa8393a51822298c3b10c91 SHA-256: 3148ac1190c9417db6e5d5c55481aac048876ec57e5fc95d53b8186302ac813d
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, appears to be a lure related to 'spss for frequency distribution', likely to trick users into clicking the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kiavysocina.cz/UserFiles/File/91407723216.pdf In PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f9413ec8d---likikurasumovosu.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16093b3e755d93---89211138492.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a8ce1adfe6---94061616872.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/e2c40051ba013a9d62b1e5ba41c4f9e7/bujibesuxejuvebimi.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210522031049853977919.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/c3ebf0340e4c873028d023d105333682/80427134728.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/grjdtg1j45e5sg1ccjot8ho6gp/35640791923.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/93120c19c7597288b7a87acc12c26385/jemadepotus.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/xokimolawarozudibija.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160703e9420c12---69269421502.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/d12b690aac08ecd9a230009182a3c6d4/leludidaj.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/4q2c74726sgq7o2mnsjjtbecg4/nevume.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/ngs5ech2nn68gi6f47222dbh6v/30585300160.pdfIn PDF document text
    • https://sport-jicin.cz/dokumenty/4153642938.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160946d5091888---pudirom.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202105/file/61856431412.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/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+use+spss+for+frequency+distributionPDF 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2D 5328 bytes
SHA-256: 6f4322cb1d4ccdcb59b14ea3a1bda223fc206e23dc1c31e66f2789a423f63846
font_01_sfnt_off0000ee6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6E 10104 bytes
SHA-256: 451d18dfffc8703adaf2ada2ba795d094f044e03b6e50e9ed266b7bd489a9bfc