Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa15ca87391e4d82…

MALICIOUS

PDF

80.6 KB Created: 2021-09-11 02:42:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5380825ce54f16436a86362141ed8ff2 SHA-1: 7e6d3cf8b8da4530c1b0e7aaaf45ce1b90cbd373 SHA-256: fa15ca87391e4d820caed4520d2cc5ebe9f37ea1a26f789a61f0bb3b45ee6311
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to other PDF files hosted on various domains, many of which appear to be disposable or compromised. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document's structure as a link farm suggests an attempt to obscure the ultimate destination and evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://airshow-bg.com/file/66697495558.pdf In PDF document text
    • https://sindhuinvestment.com/ckfinder/userfiles/files/62884707743.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/54407086502.pdfIn PDF document text
    • https://sandipkumardutta.com/ckfinder/userfiles/files/gawipepuzojifo.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132c17f916f0---24124296603.pdfIn PDF document text
    • http://vakoplus.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/kafubilukupawa.pdfIn PDF document text
    • http://thefarmatarapahoecounty.com/userimages/57939453556.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/sk7h71euvnebd8bjc88rin71na/3623325331.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/29259049633.pdfIn PDF document text
    • https://protrialse.eu/files/files/sajuwagorabukoj.pdfIn PDF document text
    • http://esllearningbydesign.com/app/webroot/files/file/49754683650.pdfIn PDF document text
    • https://strechybenesov.cz/content/62298987655.pdfIn PDF document text
    • https://chezgregoire.fr/userfiles/32074547158.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/wejunawekuwumogosovogux.pdfIn PDF document text
    • http://www.moyekolodin.com/files/17162151803.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/teturojuwo.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/lusipetibagagodekuliz.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/7b117b273bc9984cf54cb82720b38f3c/tilemorozeban.pdfIn PDF document text
    • http://zae.me/datafiles/file/firodesixabulizesuxeguwo.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161312627bba0e---fisenavasiguzipusubu.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/bcc3c3607776e8d1a4dad4ab21c3c8b4/33336077030.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/gabujivit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=no+limits+kodi+build+2021PDF 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_off0000d761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD761 17564 bytes
SHA-256: 1353156330192864b4a86bd8fdb1e8cd683e7c9a01edc5164daef2702007b592
font_01_sfnt_off000104b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC8 10516 bytes
SHA-256: a47cb20b50d883d0b3be8873684157daeeb4f231c02714ea1e8aab05e9e0f6d7