Malicious PDF — malware analysis report

Static analysis result for SHA-256 3477bb7ba7a2e2b0…

MALICIOUS

PDF

87.2 KB Created: 2021-09-01 02:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 32d982cdf956b550ebc18eb17734dcd4 SHA-1: 63347dc9b966cea010e970ea61c7bb259e3b83f0 SHA-256: 3477bb7ba7a2e2b09af530321cfb82b63e8edf2eeda0aa7b5920fcb0c0efcec0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to exploit search engine optimization or create a link farm on potentially compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://nomylo.ru/uplcv?utm_term=the+game+mystery+method
    • https://tolgyesvolgy.hu/userfiles/file/detexafumimozoxoxokuw.pdf
    • http://bigband-ulm.de/userfiles/files/xipunubugelotod.pdf
    • http://alituncer.com/userfiles/file/famubixo.pdf
    • https://hyosungulf.com/uploads/file/880475423.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072b4535c373---16171867128.pdf
    • https://bishopsalamatkhokhar.org/userfiles/file/mepedo.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0d5c8640b---mebufibewovomedavimaw.pdf
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/fupibemizanavewane.pdf
    • https://www.surajinformatics.com/wp-content/plugins/super-forms/uploads/php/files/d7a37d1da2f681f5285e3767132e3d05/51557693982.pdf
    • http://www.irrv.org/uploads/files/16145138814.pdf
    • https://client-sms.com/ckfinder/userfiles/files/wezat.pdf
    • http://originalcheck.it/public/img_admin/file///99709372765.pdf
    • http://kustari.net/userfiles/file/59540107341.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f9cc085f29d---49849713387.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/392c866ca4fe70a69e306532a8a17fce/19789603551.pdf
    • http://minhquoc.vn/ckfinder/userfiles/files/vasete.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a68c26f494---51012858096.pdf
    • http://klubalfa.org/img/userfiles/file/52065151985.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/am5649669v0j5f2mnae6bnecja/dutoduxigozuko.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b32d63df0de---73557340215.pdf
    • http://pogotowienaukowe.com/Upload/file/xikijufetimofuzik.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c201ee5ad---tutimozaposuzawutabibin.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16124b823d5a30---90231857735.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef1c.bin
5e5c170abfb677889e5467dd27b4d8034b5b16e75eda86b3be0bdf5c178f56fb
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1C 10532 bytes
font_01_sfnt_off000106fc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106FC 16792 bytes
font_02_sfnt_off00011f0e.bin
c06f60d60b8f2964e0fc71b847fb21064b9d9087fc0d501cb02be8746f625cf8
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0E 18236 bytes