Malicious PDF — malware analysis report

Static analysis result for SHA-256 41a3eb6d298713c3…

MALICIOUS

PDF

76.5 KB Created: 2021-09-10 19:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 402dde4ce6a8d76194bebd9e83caa19b SHA-1: 5538eee35d14a3c2684f498290087c405e5c5c43 SHA-256: 41a3eb6d298713c3051740199703740973cc4874251b1edf9bf7ad797d3683c6
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, including one hosted on compromised WordPress upload storage. The presence of numerous unknown URLs suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://parfumzone.ro/files/file/34276848780.pdf In PDF document text
    • http://abwrichmond.com/uploads/files/tupudoxegavinepisupolos.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/42898995297.pdfIn PDF document text
    • https://drisraadentalcenter.com/userfiles/file/sosugezuzer.pdfIn PDF document text
    • https://shatalarab-llc.net/userfiles/files/8979214925.pdfIn PDF document text
    • http://ashokarefrigeration.com/userfiles/file/58361746017.pdfIn PDF document text
    • https://nhatngudongkinh.phapluatvietnam.com/upload/ckupload/files/16506863993.pdfIn PDF document text
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/woxiveposixijoxotedinege.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/49791489632.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/rogibemolukoxejulisibunep.pdfIn PDF document text
    • http://yonezawanet.jp/units/24250/zcycom/files/jafux.pdfIn PDF document text
    • https://alpinashop.bg/files/87786672054.pdfIn PDF document text
    • https://devcons.org/uploads/userfiles/files/nigutebizaroro.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/2o0qlg4f89b5gpis879mnap4ei/88336168235.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/42187845281.pdfIn PDF document text
    • https://elperrocallejero.info/ckfinder/files/42084881344.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/monigavuzukegu.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613abd80f1e08---manumisifuwakefiwokolidik.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/5186632964.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/wifegavakejabekutufoge.pdfIn PDF document text
    • https://prettygreekvillas.com/admin/fckeditor/editor/filemanager/connectofile/56064425175.pdfIn PDF document text
    • http://parentini.it/userfiles/files/89807820099.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9bc70b92b---35082084997.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/7718686327.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/kepulenuzaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=smartphone+screen+sharing+appPDF 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://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_off0000c660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC660 17388 bytes
SHA-256: ff2fb6840643133cf3457bc79f1a2dd6efa69b7d0fe64305c36097d7a3a2fc43
font_01_sfnt_off0000f32f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF32F 10852 bytes
SHA-256: a9bea3a4ea30872335df73643cb20adf7cf6f335355bfdbe22129b50665c3882
font_02_sfnt_off00010c0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C0E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1