Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e90540a201fed10…

MALICIOUS

PDF

85.5 KB Created: 2021-08-21 05:01:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: f6a656323d0f572945292a51f5c93b88 SHA-1: f19f25289ed887928e1cd58b81a0455679928113 SHA-256: 4e90540a201fed10efda0d5af5763864bc04fa59495031c900f2a257c864a522
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://nomylo.ru/uplcv?utm_term=how+to+arrange+heroes+in+last+shelter+survival PDF link annotation
    • http://mosjob.ru/images/file/26400490845.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/surekujil.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608874b15316b---nukoko.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/tifisoxajadinejonaz.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba8817984b2---65472327468.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/1419d8132d5056f3800a401acead8efe/87541710067.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/b8eff1ce35627eda4bd929b9f29b0393/regotaz.pdfIn PDF document text
    • https://xn--80aanugxqi.xn--p1ai/admin/ckfinder/userfiles/files/pelimagol.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/37581684263.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/rahif8ccbmm7oiakd06qdlgjac/buxikiruzenabidulojur.pdfIn PDF document text
    • https://dpmceramiche.it/file/18234779013.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/jozupinagopuguro.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/380bd78b9a8e2d94c4c4b61dfa554b70/72070984927.pdfIn PDF document text
    • http://dymenahealthcare.com//upload/fckeditor/file/nuximufadisujobiwu.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/40550813517.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/woxos.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/42125694411.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/79976088226.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/20584780983.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160969083aead8---viboz.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/95290443919.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_off0000ea71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA71 17028 bytes
SHA-256: ecf113e56f689fbcef9e473e9d0ef6612771e9e95316e1b9ef7415c439c2d0b5
font_01_sfnt_off000116d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D3 10628 bytes
SHA-256: 96cca8ed7b09f1c16fe5e7257e948673c0f9411b35dcabd79e9d4f89c526e793
font_02_sfnt_off00012f25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1