Malicious PDF — malware analysis report

Static analysis result for SHA-256 24d7c90c24155aa2…

MALICIOUS

PDF

70.5 KB Created: 2021-09-26 08:20:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c444aca255ec99d48c5c7c4c08901f8c SHA-1: 9ec8b30b59ca150942b1c53d2e61e40f6ccdc2f2 SHA-256: 24d7c90c24155aa27f95774238515c1190ad13e8d8cc1f347c959e170ea4781f
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which appear to be disposable or compromised, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this PDF as malicious, suggesting it is part of a phishing or SEO spam campaign. No scripts were extracted, but the structure itself is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://krakow4you.pl/krakow/files/jigogowijelamom.pdf In PDF document text
    • http://cableesmaltado.com/d/files/4946973652.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7ddb4d342---90447099604.pdfIn PDF document text
    • https://senarathgroup.lk/assets/media/file/jamisekilivabu.pdfIn PDF document text
    • http://mounceconstruction.com/userfiles/file/jusidolito.pdfIn PDF document text
    • http://smartickgroup.com/userfiles/67565312544.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16141b9d1e77ec---xosisotupi.pdfIn PDF document text
    • http://goozzl.com/userfiles/files/xuziwezasaxanepaf.pdfIn PDF document text
    • http://balbu.hu/uploads/news/file/tinaraludedoman.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210902170731.pdfIn PDF document text
    • https://fishuntpesca.it/file/sopopexupowojog.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/wezedorukipotu.pdfIn PDF document text
    • http://apcmagon.com/userfiles/lilanaroderefixajibi.pdfIn PDF document text
    • https://durgabas.coop.np/ckfinder/userfiles/files/39455850675.pdfIn PDF document text
    • http://donghozibistore.com/luutru/files/pavugazonegarenule.pdfIn PDF document text
    • https://fleseriuassociates.ro/files/file/zefalovadeg.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/53403452493.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/muveviba.pdfIn PDF document text
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/37601190314.pdfIn PDF document text
    • http://klm-co.ru/foto/ck/files/lezevogat.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/af0ffc43bc6a92811c199a5ff18a160c/sesexezapetumimovomupoz.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/79470932307.pdfIn PDF document text
    • https://franchisevisions.com/broker-site/files/files/96379560055.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=best+file+manager+for+windows+10PDF 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_off0000b07c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB07C 11008 bytes
SHA-256: 6297ce28184c26eac241d8301079e2424ea40dddcc6a4eafd7c71019322a6d9a
font_01_sfnt_off0000c9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F4 17356 bytes
SHA-256: eeb13aa394b1e5d880e7b2d9d75776eb82c4a56b8ecc64c7a92e711ce9d12030
font_02_sfnt_off0000f4a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1