Malicious PDF — malware analysis report

Static analysis result for SHA-256 345d4ac49bf67a49…

MALICIOUS

PDF

98.5 KB Created: 2021-09-03 21:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5b0ca840a60b23e2683f3018977e6856 SHA-1: a6c42d77df7abf373e7cf237b5a108cf73e080b9 SHA-256: 345d4ac49bf67a4983a25a3ea2628fcc2ddd8e8b0ee3aa17d2393f1614c659e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm strategy. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a tactic to obscure the true destination or leverage compromised infrastructure. While no scripts were explicitly extracted, the nature of the URLs suggests a phishing or malware distribution attempt, aligning with Spearphishing Attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://krisoc.ru/uplcv?utm_term=thermistor+characteristics+pdf PDF link annotation
    • http://studiosiriosrl.it/userfiles/files/xidumiduvanaralir.pdfIn PDF document text
    • http://sztarmedia.hu/_user/file/xexixufa.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/d617ji34u11f9m9cj0n20dikg3/konunol.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/xodapemegazam.pdfIn PDF document text
    • http://www.agot.pl/upload/file/3179164957.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/86048873678.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/zexasapufezeladezumokow.pdfIn PDF document text
    • https://mtmnetwork.net/uploadEditor/files/zokenunepo.pdfIn PDF document text
    • https://kopari.hu/files/file/suxeginarirewuma.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/60553817174.pdfIn PDF document text
    • https://hetodon.com/fckeditorfiles/file/28401710921.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb3620b9c2---niribamezekabetidumok.pdfIn PDF document text
    • https://isosklo.cz/uploads/23947538890.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5d6a14d21---80721189292.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/7ee5f5d1f8a779112cf61de0a8a5a3a4/fukivufedij.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/65936701776.pdfIn PDF document text
    • http://soundreaming.org/wp-content/plugins/super-forms/uploads/php/files/6d558021f2c0a757893a0f95ed0f7296/kumulopo.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d430d027f6---jevegaselebiji.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a1f6aa989---51858774231.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///kugurafewakotiw.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf08911542---xenewutikezurobewutaz.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/ec30c4e2144f8d0db0cd0a2a7fd25c41/83262687626.pdfIn PDF document text
    • https://arket.io/wp-content/plugins/super-forms/uploads/php/files/pd0rl50hlh6p20t2qleed0nndq/jotamabimiximuborafavu.pdfIn PDF document text
    • http://3dprofi.net/images/uploads/file/varudopitudekivujas.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16072fe70a030f---pimokegolemepa.pdfIn PDF document text
    • http://d4storonto.com/clients/e/ed/ed023a0734c265ca673a92d1d81de675/File/2554228046.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_off00011bc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC6 10700 bytes
SHA-256: d2a7c8d96004bfd9dc9d29b88c415e6e26de6bee79c212e0d671adbe89e3f1ae
font_01_sfnt_off0001345d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1345D 18084 bytes
SHA-256: f20be081f2f2232e46d76bb4d3ae70ed6030fd6d05d92493a0295df3f3335e7b
font_02_sfnt_off00016393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16393 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.