Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fc4610ed78c69b9…

MALICIOUS

PDF

78.5 KB Created: 2021-09-12 23:55:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2e90585d254bae05a5d088fba196ad5b SHA-1: c140b2148cd6843725f723d0c4ff5c0084822556 SHA-256: 8fc4610ed78c69b99ba21764b91a0af3d90b998a1a1e3fc42a4c34fa9500547f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The use of compromised CMS uploads suggests an attempt to host malicious content or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=chrome+text+to+speech+android PDF link annotation
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/59311992762.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/20124648942.pdfIn PDF document text
    • http://nanouklid.cz/upload/file/wobumawawokiletunu.pdfIn PDF document text
    • http://uco-kampen.com/media/files/66838496730.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/8d520cfd42396b5a7a4ec186b9c6a852/29103243984.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbb775c22d---87365415987.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/xukojinuforituzowex.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/43685118368.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/bopaguremora.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329d4e3d2bf---94147804730.pdfIn PDF document text
    • http://jj-metals.com/userfiles/file/2021090804023473499.pdfIn PDF document text
    • http://yalcinsezer.com/upload/ckfinder/files/55170756578.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/xorogu.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136dc5b1caff---favigipasogu.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/52596781241.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/84590415269.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/21791576559.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/79887012243.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/4628904171.pdfIn PDF document text
    • https://brs.jo/userfiles/files/70893870590.pdfIn PDF document text
    • http://heatherjansch.com/ckfinder/userfiles/files/19211816592.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_off0000cf52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE769 10864 bytes
SHA-256: 89fb405ad45decdc231754b875155352711f1a3921d45898a836892766122f2f
font_02_sfnt_off00010065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10065 17368 bytes
SHA-256: e3973e404a35f80b9fba748f2c0efcc4dc87c30cfe0dd3b5c64e3c9bea76d8a2