Malicious PDF — malware analysis report

Static analysis result for SHA-256 e665543f98d590f0…

MALICIOUS

PDF

76.4 KB Created: 2021-09-12 14:37:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a89c5e3e62fa2feba6ec8e27a4de732e SHA-1: 74595603a2b1608608812a1c1bf0af8801cbdfff SHA-256: e665543f98d590f077e51eca727bd1dfe8e389cc446cff93d9af1a79b2859ceb
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs that point to other PDF files. These links are hosted on various domains, some of which appear to be compromised CMS upload directories, suggesting a distribution mechanism for further malicious content or phishing attempts. The presence of multiple external links and the 'link farm' heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://phantasos.org/userfiles/file/60831708868.pdf In PDF document text
    • http://lagostena.it/userfiles/files/68391933417.pdfIn PDF document text
    • https://sma-dfgg.org/site/admin/file/38241304824.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/45573247642.pdfIn PDF document text
    • https://csmgh.net/pevron/www/img/file/zojelesonapopasadogetok.pdfIn PDF document text
    • https://medpressa.ru/files/file/xajigipixedid.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/95651352807.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/bowetirukokesadajev.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/2356286afcd017b577fd4ec54bcfc447/werorolidaf.pdfIn PDF document text
    • http://riviera.az/userfiles/file/87871545403.pdfIn PDF document text
    • http://aktifithalat.com/resimlerfiles/1752605205.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/e6197dde7d9cd6bc986f09ce72094dea/7320940331.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/d81ba04eb11cdea3799800bbeda04ca4/61190424531.pdfIn PDF document text
    • https://z87992961.com/upload/files/20210904132036.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6037993e---59792566658.pdfIn PDF document text
    • https://zhongzing.com/uploads/files/202109120419191295.pdfIn PDF document text
    • http://trieuduong.com/images/Download/64918831476.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/fudajuzojofojib.pdfIn PDF document text
    • http://osayit.com/images/file/zoruvewinogozadazoname.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/69258407140.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/guzef.pdfIn PDF document text
    • https://theelementrama9.com/userfiles/files/15118254574.pdfIn PDF document text
    • https://deepex.hu/hirek/files/42842350926.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=top+aeroplane+gamesPDF 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_off0000c72e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC72E 10368 bytes
SHA-256: e698106426dd2bfd557f526325826a6ccac59f8dec43de89d39ec2c0526f95c2
font_01_sfnt_off0000de95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE95 17688 bytes
SHA-256: cf8d589da933a3a622a2772747bd482e45358dfc5bb818c5bdaffa38e87c2551
font_02_sfnt_off00010c75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1