Malicious PDF — malware analysis report

Static analysis result for SHA-256 31293037f7d775c8…

MALICIOUS

PDF

72.7 KB Created: 2021-09-14 15:04:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: afa84f365454a86b66c4d772a1015db6 SHA-1: 3d46ecc318d982afaa780c3b0c872aed86935923 SHA-256: 31293037f7d775c87329b2ed1a970c833d5e31f9b5873881249261549f964a50
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is part of a link farm on disposable hosting, pointing to a phishing or malware distribution scheme. While no scripts were explicitly extracted, the presence of numerous unknown URLs hosted on various domains indicates a broad attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://hanauhrova.cz/files/dilerakivapajam.pdf In PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/lubafaboluwawedow.pdfIn PDF document text
    • http://f1-rennsimulatoren.de/userfiles/file/91764257871.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/77171292400.pdfIn PDF document text
    • http://photo-ostrov.com/ckfinder/userfiles/files/fidivowomizebakokaf.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/4abc84f5f5154e765010f2597ac4d4ab/52320020516.pdfIn PDF document text
    • https://nistd.in/userfiles/file/66435529829.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/gafijenutirepa.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/zabujido.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/161402030eff05---tukumi.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109022246122674.pdfIn PDF document text
    • http://veterina-hrib.cz/user-uploads/files/rowafanijefox.pdfIn PDF document text
    • http://gs-metals.com/filespath/files/20210911093755.pdfIn PDF document text
    • http://mallorcaboom.com/res/wysiwyg/file/gusiweboragelelufovew.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/19379195819.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/55839774119.pdfIn PDF document text
    • http://houtackers.nl/userfiles/file/pajowidan.pdfIn PDF document text
    • https://998.geektic.com/geektic/files/kifidibaj.pdfIn PDF document text
    • http://zhxndl.com/uploadfiles/files/25368902157.pdfIn PDF document text
    • https://abhimaninteriors.com/ckfinder/userfiles/files/36859430490.pdfIn PDF document text
    • http://giorgimpianti.com/userfiles/file/zumaxowegatitu.pdfIn PDF document text
    • https://xn--atpta-nfb.lv/images/userfiles/files/pudexan.pdfIn PDF document text
    • https://biocoils.com/img/file/kigori.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/19157876538.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=watch+it+chapter+2+123PDF 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_off0000b8a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8A4 17392 bytes
SHA-256: 406a17ae17c90244e5563e6a1eedd23a1598c2ac67fa1c5d29d1e10c5d4e9c5c
font_01_sfnt_off0000e568.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE568 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7F 10372 bytes
SHA-256: c9360ba91e4276a681f1ea727c676b13799c11d0a0cef4a1b944e122f9899d1f