Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6d2ffe09b8899cb…

MALICIOUS

PDF

82.5 KB Created: 2021-09-18 00:11:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 82318cdc7e64c4d98807c34d0efa846a SHA-1: bec08e4127d0d40c535cbd0aead8676db654e82f SHA-256: b6d2ffe09b8899cbe5f62a5cb3aab8eb3a6bd7b0eb8c87b0c35c7449af3eb71d
156 Risk Score

Malware Insights

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

The sample was identified as malicious by a ClamAV signature and an ML classifier, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, characteristic of a link farm designed to redirect users to malicious content. The PDF structure itself appears to be a lure, with the document body being unreadable binary data, suggesting the primary function is to host these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://abandassociates.com/ckfinder/userfiles/files/xufunivo.pdf In PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614334a4f0126---88684996275.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/94188284587.pdfIn PDF document text
    • http://rurisnet.org/images/file/xawajobijilobogufenek.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/93496789484.pdfIn PDF document text
    • http://xn--q20b13r9leepaeb.net/upload/file/202109060614333994.pdfIn PDF document text
    • http://studioingegneramato.com/userfiles/files/nateparagisikewozuxi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7e9d124c5---wugawuw.pdfIn PDF document text
    • https://pratham.one/file/83141275437.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/88483766903.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/pasenexuwazora.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/4e5a8e2f37f2977ad0ff910c0328c5bc/buvevof.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/4pd0ut1bpofipvlk5d64thtaar/nuregewimagavamevoroti.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/96194399769.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/muxusor.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/bedugagos.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kisoko.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/86860333592.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/mafejadusujug.pdfIn PDF document text
    • http://packturf.fr/files/94004368057.pdfIn PDF document text
    • https://shturnev.com/files/foFKED/file/44699168445.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/dodivojusupa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=watch+mulan+2020+freePDF 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_off0000dacc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACC 19084 bytes
SHA-256: c91e9c3be431bcc31c7f30cb3821030bfd702beb3380b059dfe6758f986532b4
font_01_sfnt_off00010cf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF8 10556 bytes
SHA-256: b127f1c6c7c838ee5d879f5af246a524b20f8288d88fd7f0889f6ee2d29eb2e7
font_02_sfnt_off000124f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1