Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ba594a6234a8d8f…

MALICIOUS

PDF

104.6 KB Created: 2021-07-12 17:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 932cb3c23051d05ac29b14957d2ea125 SHA-1: f66f5befabb137030e3b478797af3600945307d7 SHA-256: 8ba594a6234a8d8fbf1596e065fcf26c9ea9f910ed1abd4a94e04a266713463b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress upload directories and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and the nature of the heuristics point towards a spearphishing attachment as the initial attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://inwebjor.ru/uplcv?utm_term=prevalence+of+tuberculosis+in+ethiopia+pdf
    • http://bigband-ulm.de/userfiles/files/vezelikibolide.pdf
    • http://serramentisiciliano.it/userfiles/files/43330028556.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c805b4abce---28638094359.pdf
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c51577126---xogeju.pdf
    • https://aduanaldelvalle.com/userfiles/file/10476909449.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f784dd0706---64146941326.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/9s2crctjnbatjrk7q1vs2462t5/11519113121.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1e38e1c61d---xusizezenizuxopamuf.pdf
    • http://beateromer.com/bilder/file/valuke.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/palikuriri.pdf
    • http://hosungtour.net/FileData/ckfinder/files/20210620_CC70218F798C2931.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/228160fa104a0a0d4e21f0bb3d4a617f/12645736586.pdf
    • http://anhuicrew.com/upload_fck/file/2021-5-16/20210516223433515931.pdf
    • http://kpdb.org/userfiles/files/zosizusuvudigeti.pdf
    • http://sweetbasketsbyjackie.com/clients/864293/File/91367159078.pdf
    • https://arnetbilgisayar.com/upload/ckfinder/files/mifevirawipisewamu.pdf
    • http://hoadondientu-ptp.vn/images/ckeditor/files/9336063847.pdf
    • http://aftckwt.com/uploads/file/38052848817.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/508ec81e4845924a45bde9062252d53b/wugirelozoduramidemiru.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e4d93313731---musov.pdf
    • http://zimaletto.com/uploads/file/wupugoninudavototavub.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608024e289103---tegafasuvuzumotaw.pdf
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/jowikokon.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c28d494579d---ramopiga.pdf
    • http://amdind.com/userfiles/file/85721570972.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_off000134a0.bin
d6cc0d36f6ba7b0d985500ff931b36792e67e81c003ce45164dad621d7347987
pdf-font-stream PDF embedded font (sfnt) at offset 0x134A0 17812 bytes
font_01_sfnt_off0001636d.bin
1fc73182590187880126e03ee6f51c1d7fdff53064c402ad664ee9aa467e98c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1636D 11024 bytes
font_02_sfnt_off00017cc5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17CC5 16792 bytes