Malicious PDF — malware analysis report

Static analysis result for SHA-256 581f4ebb5ce92fe2…

MALICIOUS

PDF

73.2 KB Created: 2021-09-12 21:45:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 399a79ca53ec6cce23ea7ed88e5a0dcd SHA-1: 11141fa09f9f62573823a0f504630ad998f07f31 SHA-256: 581f4ebb5ce92fe2fe27f1e31b2731f80470fda9f4749a8a5ff4c7214e0f388c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of embedded JavaScript points to T1059.007, and the overall nature of the document as a lure aligns with T1566.001.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=two+letter+words+beginning+with+y PDF link annotation
    • http://dakdekkersindex.nl/images/uploads/84671099400.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/jijivomipebuxamesagida.pdfIn PDF document text
    • http://emusicmarket.com/upfile/board/files/79849722129.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/b3eb98206a959585727e153adedbac15/matirulod.pdfIn PDF document text
    • https://pixel.bg/img/file/gasinapal.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/30010197778.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/jobowotop.pdfIn PDF document text
    • https://shibbirs.com/media/files/kigawojibirazabevuvexadez.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ecd2e9bf5---86218151826.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae5334c786---2452664954.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/dc4d569754cb8145beb67498934f36ed/luziwiwonez.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/08c773ad43006a992cb1ffd947ec913f/buvegevafosividomikilopo.pdfIn PDF document text
    • http://captaincook.hu/userfiles/file/52681617337.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/seladiwaxifefisuru.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/3292271330.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/7724652520.pdfIn PDF document text
    • http://autofactory-jin.com/js/upload/files/68451794203.pdfIn PDF document text
    • http://rotarytattoomachine.co/project-new/christianbook/upload_images/file/4209656189.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/74272715633.pdfIn PDF document text
    • https://czus-lukasa.sk/userfiles/file/89186605720.pdfIn PDF document text
    • https://barrierball.cl/ckfinder/userfiles/files/3619936143.pdfIn PDF document text
    • http://architettosirocco.it/userfiles/files/davisalenatetezul.pdfIn PDF document text
    • http://synergienetwork.net/userfiles/file/wapuvinej.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_off0000b99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB99B 17384 bytes
SHA-256: 6018c4a9ef4067cb2a28e2e5ec02cb461fbac622d3f7cb17e421b4dd32675341
font_01_sfnt_off0000e70d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE70D 10668 bytes
SHA-256: 6fab94fe3985f7e1ea65ea830d479518b3f50bd68bafa2f15bd9f626cf5da0a9
font_02_sfnt_off0000ff3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1