Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9a57cd93e0705bc…

MALICIOUS

PDF

97.4 KB Created: 2021-07-17 03:08:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b18ad7c46e08cc4d90762759e8355616 SHA-1: e23c8aeab331fed880899abac1a38d172c501ade SHA-256: d9a57cd93e0705bc71b09911b295025935a166ed66d800beaacf27fa56285d18
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm or SEO poisoning tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://klusjesindex.nl/images/uploads/7806273058.pdf
    • http://accessiblevehicleservices.com/userfiles/file/xadiwanitevinezoridef.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/94a30ae5fcedbf49ecd84b0a08ca24a7/77001606664.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a179d1edc---javepagevegalano.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606caeb7cf22e---36555020454.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/j13u7gs48i1nup395tp55pkhdr/juzabazidif.pdf
    • http://harrisonfamilyreunion.org/clients/868801/File/tusebazavabimegutituf.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/sn6gnuh6366qjdfv6vttn7vegn/1226484593.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a967e77d0b3---kisojebepikafivajoduf.pdf
    • http://benrassam.com/uploads/files/30577113414.pdf
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/n9urbo9cfh288ur1atjsgus4cv/musozisozaxatofuj.pdf
    • https://www.ijmsir.com/ckfinder/userfiles/files/wexutawajotateri.pdf
    • http://artecgroupservices.com/imagenes/file/gurijenepovoxurifejuk.pdf
    • https://cissud.eu/uploads/ck_editor/files/10464950887.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b09fb030593---90868007994.pdf
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087388165021---gurugiri.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/49196848249.pdf
    • http://vodnik48.ru/content/file/87808628173.pdf
    • https://alice-immo.com/userfiles/file/39074693858.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/39sb283rn2ohtvg1jb3u2do32l/56380911234.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160753957c4bc2---20943280534.pdf
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/v3tcfp3pkkr6okbkh7qbqhm88i/bunit.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607caf1ec4818---xukalep.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+get+dog+poop+out+of+clothes
    • 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_off00011b19.bin
7cd8f73819609adcc6f83e97fda7ce4e1d282b622cc12cbfad2bf3a0c79f374a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B19 17244 bytes
font_01_sfnt_off000147b7.bin
3860363a9823b0a339f3bd8345c8a82252a8e0fb746f4a8b7a7bb882377cfda6
pdf-font-stream PDF embedded font (sfnt) at offset 0x147B7 10620 bytes
font_02_sfnt_off00016003.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16003 16792 bytes