Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ded751f484692b2…

MALICIOUS

PDF

74.8 KB Created: 2021-06-21 19:05:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5fc48649da6fd4f62722003da63fcf98 SHA-1: 850f473f4ee5d75ffc598ea840b3a8e4cd1e98fd SHA-256: 3ded751f484692b23c00f228ca75ccffa509f88c1d6954c70305bf9f0400af9e
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to websites hosted on compromised WordPress installations, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and appears to be junk data, but the presence of link farms and compromised hosting is sufficient evidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082656b46115---6246940381.pdf In PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/3661a58746d3bc1901502f7e714938ff/zusisawudenakijeraruviven.pdfIn PDF document text
    • http://hyperasp.net/userfiles/file/92425930016.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16208694115915.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/kovavonevu.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b3ffa486e46---fupavedim.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/h6ioqhls93b4p83e0i0b8o3l54/wukipizolexeje.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607cae941281d---xuxejixow.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pcei53qv0clda5r7u6c7v0nr65/jimuzomuv.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/bd6932d90759405aed26c2c44dce0644/431671872.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/ad25a0a87681a5d3b8b2cf486fc0adfa/13688320214.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16070ca5ac42c9---40169399299.pdfIn PDF document text
    • http://armanetti.com/images/daliwelowofujatuzog.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/110538167671.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/96547165228.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/17310643387.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5e5763d36---73720816816.pdfIn PDF document text
    • https://coopinproject.eu/ckfinder/userfiles/files/rawis.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/sg0bc3qr5jruh1epr6t1g9383p/gawiforomolopuladeba.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/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=dragon+slayer+2+quest+guidePDF 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_off0000e616.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE616 5352 bytes
SHA-256: 7892798b3d118bd755f18da8d8377d7d867866b54842db19e854e1455974185f
font_01_sfnt_off0000f85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85A 11940 bytes
SHA-256: 34b8b752a43a8e4fe77e7c891a85fe415baa3047a89dbbec5bf92fbbe316e965