Malicious PDF — malware analysis report

Static analysis result for SHA-256 63e0e1b13975ff96…

MALICIOUS

PDF

77.8 KB Created: 2021-09-09 23:25:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9a6ca45a8bdd5ae073cfd0a5fd336559 SHA-1: 9ec8017c170e4ac7c727fcbe0cf96414a17f05c2 SHA-256: 63e0e1b13975ff961129c0febb6c1c0de7f433113aec063b61e632aa351f77c3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, suggesting a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using numerous distinct hosts for redirection. No scripts were extracted, but the presence of external URIs and the link farm structure strongly suggest the PDF's purpose is to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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://kieryk.pl/img/userfiles/file/futigosufawopaza.pdf In PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/74779855214.pdfIn PDF document text
    • http://wohingltd.com/userfiles/ripuwixigefugit.pdfIn PDF document text
    • http://rafaelokazakov.com/file/59074244288.pdfIn PDF document text
    • https://kenhquangcao.vn/uploads/files/35772619980.pdfIn PDF document text
    • http://harryreichert.de/uploaded_pics/News/file/retosesovapema.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/dalerikexemufikigow.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/g8l026dplt39aep0qvdufpkrat/99705212791.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613109e5338b1---kovat.pdfIn PDF document text
    • http://xn--80aguejfegacgj0ad.xn--p1ai/pict/file/gatinijap.pdfIn PDF document text
    • https://beaszemin.com/files/94378222506.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/97656340632.pdfIn PDF document text
    • http://oresteruggiero.com/userfiles/files/14472126816.pdfIn PDF document text
    • https://geniodelweb.com/file/wexivel.pdfIn PDF document text
    • http://www.ezmoving.com/file/29818555674.pdfIn PDF document text
    • http://www.pilatesyoga.hr/files/files/xopaw.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16139357f07262---lanegenukojiti.pdfIn PDF document text
    • https://hoavily.com/uploads/files/luledumixofimazepumomafa.pdfIn PDF document text
    • https://wspaperbag.com/userfiles/file/32844677694.pdfIn PDF document text
    • http://nieruchomosciklodzko.pl/files/file/lovevigojafovepezadojebad.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/kupexaxuzakikanawojobipab.pdfIn PDF document text
    • http://alotercuman.com/ckfinder/userfiles/files/lufopemasabovugulodivepe.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/pinim.pdfIn PDF document text
    • http://enricobarraco.com/files/36438123147.pdfIn PDF document text
    • http://ranch.pl/files/file/78027086089.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=hacker+baba+linkPDF 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_off0000cd81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD81 10060 bytes
SHA-256: fd46911b43c8a2a3a12778a212f59587f776f96b63490cdda5baa986b9280bec
font_01_sfnt_off0000e3e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fbf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF8 17548 bytes
SHA-256: 5216ff7067be32355c74bd2f902be6ad489e45c375089b6e3fbadcd22d076da3