Malicious PDF — malware analysis report

Static analysis result for SHA-256 53cfa5d3f3e81956…

MALICIOUS

PDF

93.6 KB Created: 2021-07-22 12:37:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5fd852bcc159f19c0cf3b69972fa3772 SHA-1: 41c50de72119f81c40e0eb8f7ed46fb3706ae5bb SHA-256: 53cfa5d3f3e81956dce12bb039df1e6c32fbfa1370db234ac97d862f0e30cd4c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links pointing to websites that appear to be compromised WordPress installations, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this file as malicious, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The embedded links are likely intended to lead users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/eheov7ae1bd76m8opsvlrvu3da/gafuvodonoruvazepunizi.pdf In PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/642187ab9da17b3a0bd989dddad811f6/1516962580.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/tijeneralekatixigidizet.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/8be7946cd4e3072389fd0965df5af5ee/kebejoradepukiwadutajaru.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/vetegafaluzekixisukof.pdfIn PDF document text
    • https://leuphuotcamap.com/uploads/image/files/46590362859.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/nemesigimo.pdfIn PDF document text
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/6068136d4d3cf4b9c2fbd6c04580cbd9/31897828530.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/4ec83b55b3dee7a29c155ae23bfc26ea/8479527821.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160dc38800118e---59848295524.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607002dd80bae---31708348017.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f76735c0c6---gupomemutonoludugoraxifi.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/fm5ne91g5lb6u47pfl1dov7lkv/25677057500.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/8fdd649fe6bce4623c3128b059c27fc1/tugiwapejujopilesobugexo.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160815fba0e272---24455591097.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/48943007707.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c7e917880---tativepogitame.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/839bc424b32af7c71a75716690920a93/6539823852.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/xufizopizab.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/868e966e4ffcff63d33c928ab625bd48/57647570293.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/d5134893ae161e849dd77f19e78aa49b/gapuj.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/54259458260.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/ddd162ebf3520b108be0d2b10427fbb1/jerut.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/zalovanoferuxa.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/fhldhcgul8didmm0le5hsfqm73/73591875778.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=earth+day+cleanup+near+mePDF 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_off00010a29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001223b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1223B 17664 bytes
SHA-256: 155d3b23e4bef1a5779ce4216fd8081252283db27f1b931d6b5a063401bf1667
font_02_sfnt_off000150ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150AE 10596 bytes
SHA-256: 11d8bec3308858210a612d06b9abab2eeae230c8d6526d458ae0d96344eb4dca