Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c221573825a38f3…

MALICIOUS

PDF

72.2 KB Created: 2021-06-24 17:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 6c61b3864f11b3780c058abab11fadf9 SHA-1: 5ba758334f71adc9ef22ab7fa218fb08b4742759 SHA-256: 4c221573825a38f338a86e608fea9888dad7c8b401fbc6a812452dc2a668f63e
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be hosted on compromised WordPress installations, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The document likely serves as a lure to redirect users to malicious sites, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/9qopdlpl2pgvq5461sa4f0kcmq/navuri.pdf In PDF document text
    • http://podushka.by/files/files/82587495294.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609837519f6ce---zediboverukabutexib.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/2cb86b76fbbeb7b95a3d97378ed4895e/jigufimikumobisemure.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/77638140432.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/3uhmdrukcmitevii8b7ci2gkl0/pufabuviwanarefureso.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/94561987830.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609046d67fecd---gezofivizejanemipapenub.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/97044978.pdfIn PDF document text
    • https://kurtoglumob.com/upload/file/27302468341.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/29428d8f98bd06e3e560329c78512588/11503079208.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b65d1117309---mokibiga.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c77629ddf6---fevele.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/ee43c0027a834b5d43ef8bd5ce37accb/relulik.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/4a59b1bb710a0c1a5fc90a472d5030cf/51375939967.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/puvobivirikavumog.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=condenser+pdf+filePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB4 4728 bytes
SHA-256: 19043baf796ca8b7dcc726a075fde03f7ed6446ba5d54b6215c0279df102641d
font_01_sfnt_off0000ecd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD3 11132 bytes
SHA-256: f0622cac0d8e118dd48c9cef1396ea4f593a5a64bf8cefd25675f43bfbee6162