Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed0f0558c271ff5a…

MALICIOUS

PDF

89.1 KB Created: 2021-09-19 17:57:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b7d38fdf94b8d1c655996ade252e99cb SHA-1: a1234b41967756cbe499762b00681d69cb858d4c SHA-256: ed0f0558c271ff5af2ed835f513ec807404d680fe87ba52c2cc7c2ec41d98016
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding a large number of external URIs, likely to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://archism.ru/uplcv?utm_term=best+android+games+for+7+year+olds PDF link annotation
    • https://duocvinhkim.com/userfiles/file/52893189418.pdfIn PDF document text
    • http://zvaracskaskola.eu/editor_uploads/system/files/47275858840.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210911045920.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/vigogeviwotewilozalula.pdfIn PDF document text
    • http://solee56.com/ckfinder/userfiles/files/nuxawetegakener.pdfIn PDF document text
    • https://nusbetaja2.com/contents/files/semumarorarabekejil.pdfIn PDF document text
    • https://lifo-sea.com/ckfinder/userfiles/files/52779959295.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/25355053327.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/85618597105.pdfIn PDF document text
    • https://penzion-palice.cz/content/36464729589.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/89217426368.pdfIn PDF document text
    • http://dynamicyunnan.com/ckfinder/userfiles/files/gosezaretewivizazumaged.pdfIn PDF document text
    • http://affectif.ro/data/Image/file/razifeni.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/suriwubuturitag.pdfIn PDF document text
    • https://rajatotogroup3.com/contents/files/mepozase.pdfIn PDF document text
    • http://ridendo.cz/files/file/21678873114.pdfIn PDF document text
    • http://skrn.cz/pic/file/5066917736.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353eb3b6e9c---46809294303.pdfIn PDF document text
    • http://xdata.pl/app/webroot/img/ckf/files/20009042495.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/roxefuk.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/25515470bbae1427bb4cfc1a9737510c/3904929551.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/jikifa.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210902175625_1893804029.pdfIn PDF document text
    • https://globalcareerclub.com/FCKeditor/userfiles/file/nabosezuluf.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109061018022121.pdfIn PDF document text
    • https://nergizleryapi.com/image/files/xinajuxorugaw.pdfIn PDF document text
    • http://royalleasingny.com/admin/images/file/bilulabiginuw.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/1429700557.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_off0000f9e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E9 16604 bytes
SHA-256: 8ccf60e496c5ff24d05f809d079b96b829dc5078725ad5dabbf190dd13ecb9ce
font_01_sfnt_off000124fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124FA 10916 bytes
SHA-256: 03e2d091957e9d31c80b8d2328c7c1b53b4d7e52098ed8e368010dadfa096b8c
font_02_sfnt_off00013e24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1