Malicious PDF — malware analysis report

Static analysis result for SHA-256 f43133c504b31ddb…

MALICIOUS

PDF

84.3 KB Created: 2021-07-16 01:34:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a61be9178417966cae4f1546da8e189e SHA-1: a004d54b49065b0a7470209602cd4714c4c8b745 SHA-256: f43133c504b31ddb6585525e2a13faf6001fcd53b51a01030f9179b181a70fbd
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to compromised or disposable domains, indicating it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest a malicious intent to redirect users to potentially harmful content. ClamAV detection further confirms its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://cructi.ru/uplcv?utm_term=runescape+stronghold+of+security PDF link annotation
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/107c5a108598dd68b6e733131f1db97f/21310509226.pdfIn PDF document text
    • http://massimoandyuethui.com/clients/69227/File/71780845363.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/45455734840.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/cpekn2lrte96d3gad3tiq6u5r1/60771245398.pdfIn PDF document text
    • https://orangerun.re/photo/files/84304957924.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/72977388158.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078bd62e0a68---gufazobal.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/46334dc5db9615d5ac4e6394489692d6/89808160887.pdfIn PDF document text
    • https://proxus.nl/file/44893494362.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/95880923508.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/lifunufawebat.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a076d377d5a---nixamuwitozexefufogi.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/begirejetarazufo.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608218a54d0fc---dizarotixazejimixeno.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dca221a5a0---sakukibujitav.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/42018381698.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/nn9bcfv4grs09c6hocecbolum5/98250167160.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/3r6tdfmjl3p0utok07vh8r72sg/lexovivedeba.pdfIn PDF document text
    • http://paoladebenedetti.eu/userfiles/files/dubog.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_off0000e6f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F4 11160 bytes
SHA-256: fc3105df5eea651c9ab833675bc5629eb3e57564c66f35ef5b868a3db72b215e
font_01_sfnt_off000100cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118DF 16956 bytes
SHA-256: 5fbfbfe153bba6cc717727913bae0e3e01d8827d36ee8f4642b3a0aa1027ae9a