Malicious PDF — malware analysis report

Static analysis result for SHA-256 8031fcfb4c446087…

MALICIOUS

PDF

80.7 KB Created: 2021-09-22 12:45:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fae5745718ad6ceb1d0734453f77b27f SHA-1: 6dce7533e512511c039d887fedcc12a3de38e1dc SHA-256: 8031fcfb4c446087ebfd648134bd0b3faa153cd069163de7310df1b822469f0b
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm. Some of these links point to compromised CMS upload storage, suggesting an attempt to lure users to malicious or compromised sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://bayanairag.com/uploads/userfiles/files/gulejokaxumidurovuxopepi.pdf In PDF document text
    • https://cuatudongsaigon.net/uploads/files/83950889200.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/nuvev.pdfIn PDF document text
    • https://manorhair.com/uploads/files/202109161504102435.pdfIn PDF document text
    • http://cloudinfo01.smartevolve.com/images/ckeditor/files/lizadumerewodaloro.pdfIn PDF document text
    • https://tamphuctriland.vn/upload/files/6525426928.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/90170843971.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/65107799734.pdfIn PDF document text
    • http://smalternatywa.pl/media/upload/files/cbb4d0f7e1187b91d7a8b6a2e10372bd.pdfIn PDF document text
    • http://kssi.ir/public/userfiles/file/62930691390.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/901dc8000c383f2f0da357a03c041593/55599140370.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/85170926761.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/lakowusin.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/97494358828.pdfIn PDF document text
    • http://esistore.be/userfiles/file/68586507895.pdfIn PDF document text
    • https://peterdegendt.be/file/jiketikizofirabexurelekin.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137bef1bad9b---35038443283.pdfIn PDF document text
    • http://novena99.com/uploads/files/202109051909216393.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/volipanisewelimatafezel.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/37044972100.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/20219132316404257.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a9c248c43---54878143394.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/15862384415.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=best+free+movie+download+appPDF link annotation
    • http://pro.ovh.net/~tribuene/images/banque/file/68672855339.pdfIn PDF document text
    • 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_off0000d5c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C8 17884 bytes
SHA-256: c97bc28a9fa5e332c3f96e517ca51b74f7b68c8c3cc2da0ef3530382c8a4efc8
font_01_sfnt_off0001045b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1045B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C72 10864 bytes
SHA-256: c3d41fe6b8813615764c013c5c0f433ef9fbdd6e7d502c3ccb42ac2d17b82d6c