Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e58f23a408efcdd…

MALICIOUS

PDF

74.1 KB Created: 2021-09-06 06:26:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 72cf6a7a7eb0fa14f6f0bd6f4d9871c2 SHA-1: 5cd6be01682b9e40e1ffd655c677eb7cc1297a0b SHA-256: 0e58f23a408efcdd259a09a0f8f71780369f588a639127d59a7b1013cc134a42
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The presence of numerous links and the use of 'utm_term' parameters suggest an attempt to manipulate search engine results or engage in phishing by luring users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://truongthanhco.vn/webroot/img/files/rukabegiz.pdf In PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/mf6d2dl10bd8fc1ugc79onu4r6/gonaxasu.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/46129801608.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080285fb172c---rewokokixazireva.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210726005734.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/tasudedupajepiwojud.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/97031168786.pdfIn PDF document text
    • http://biomehl.com/images/content/files/nenegon.pdfIn PDF document text
    • http://circuitoinsulargc.com/documentos/file/90348389383.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/cfc29fe2b5f908e46f93619744903886/12799136069.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4a5396bac---vajixajurobedanepusatokuj.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/ac37e6b49ebe0b0fa9c797b7669b9b94/24472666347.pdfIn PDF document text
    • https://triosms.com/userfiles/file/20740641602.pdfIn PDF document text
    • http://zubrcup.by/files/files/11496288667.pdfIn PDF document text
    • http://onlineexpert.in/userfiles/file/xokomej.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/37890919766.pdfIn PDF document text
    • http://cyuansheng.com/userfiles/file/fonafezivefaweve.pdfIn PDF document text
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/fazulabuvitigumi.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a230b23afaa---tusani.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/naxoguvadopuxiru.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/6e75fe6b4557096cb724d6dcbf70022c/72433553455.pdfIn PDF document text
    • http://cuacuonnhanh.vn/Images_upload/files/wevasikokafupuna.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=chicken+biryani+seivathu+eppadi+in+tamil+language+pdfPDF 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_off0000b8ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D1 11488 bytes
SHA-256: bad9bb8ab8a7e0ac82e5db8c9c2062eab20706ac75439d4b45926339c5ee7c27
font_02_sfnt_off0000eb6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6F 18068 bytes
SHA-256: 4997f6ef1c915e0f50e1a2171b4e025e1a56c780f7eb40960f6e8e581a03a590