Malicious PDF — malware analysis report

Static analysis result for SHA-256 4db67af6e42e3840…

MALICIOUS

PDF

84.0 KB Created: 2021-09-08 09:28:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 85654343061948c777e35fc7e38219e6 SHA-1: 86de4d70c7cb9228f94a54f9bc18ea39e653b120 SHA-256: 4db67af6e42e38404c0c543d3210b3d792afa6a6582b9a5505c30e721fb002d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous URLs, many of which point to compromised WordPress upload directories, suggesting it's designed to lead users to malicious content. The PDF structure itself is identified as a link farm on disposable hosting, further supporting its role in directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f25cc05804---dovorulameruxeg.pdf
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/28214276524.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/suvezipoperamazibozot.pdf
    • http://dush-kz.ru/uploads/fck/file/vukusazusajure.pdf
    • https://tyeetomsfishing.com/userfiles/file/9881948956.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee44c502b6b---27479233975.pdf
    • http://china-zub.ru/userfiles/file/46883463466.pdf
    • https://heart-calligraphy.com/uploads//files/202108110749091369.pdf
    • http://www.huntsvillepr.com/files/files/zaxobamedidijumopolofiri.pdf
    • https://omnistopbollards.com/application/third_party/ckfinder/userfiles/files/jugogojurokew.pdf
    • http://safedoorsystems.com/cmsimages/file/9994976892.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7ac855d18---xifesofumipo.pdf
    • http://www.sudaff.com/pics/file/35378247546.pdf
    • https://agrilaui.com/userfiles/file/65998798929.pdf
    • http://msslink.ru/userfiles/files/jimefokeguwubogoturid.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/cac7117f8aa56a94eec74ef3b4b79c79/75559938838.pdf
    • http://www.lircai.com/web/inline/file/44522932375.pdf
    • http://beloezoloto.ru/userfiles/file/79576691198.pdf
    • http://minisadik-margaritka.ru/admin/ckfinder/userfiles/files/82109739427.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/824o8c0u5u2tmf2aht9dd9cih6/20749553375.pdf
    • http://wadsoda.com/UserFiles/File/jatetemubigamuzimam.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbd1e429494---tariwugupedaradoleki.pdf
    • http://khodahoanglang.com/admin/webroot/upload/image/files/11995701358.pdf
    • http://marchmontnews.com/imgs/file/nitivakokesisalukazifo.pdf
    • http://cukiernia-waltar.pl/qcms/userfiles/file/vasabitevizal.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c87643348fe---7796954408.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=multiplying+and+dividing+fractions+practice+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_off0000de0b.bin
560135a169659b20f02297f6c6cd84faa31e8f731ebb35b73380280c2a201a90
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE0B 18884 bytes
font_01_sfnt_off00010fac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FAC 16792 bytes
font_02_sfnt_off000127c3.bin
63d6eaf0ea6c899ddb40a8fb0dc8efa41a002cbc28cd4b4e2825d8abcae0d807
pdf-font-stream PDF embedded font (sfnt) at offset 0x127C3 11068 bytes