Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c7901759085dd68…

MALICIOUS

PDF

85.0 KB Created: 2021-08-01 13:34:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bc2d53d15b30e506e84b8d32e5705851 SHA-1: 82549278c921ac7c893f6d897d9c2d9fe9370c53 SHA-256: 8c7901759085dd6848bbda4f09564d44a8f5f0f15050d85f0b99dd187ed955ee
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites and disposable hosting, indicative of a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://excore.hu/ckfinder/userfiles/files/sibujifewumebi.pdf In PDF document text
    • https://louvre.lv/res/wysiwyg/file/41275693056.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/c2c9c4fb20d6e5edcca1d9384a7f655c/95776282753.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/fivedawemudefov.pdfIn PDF document text
    • https://evenimentecastel.ro/wp-content/plugins/super-forms/uploads/php/files/56rfpu96ir3q7q4sm7v3elc70o/venesubaladux.pdfIn PDF document text
    • https://healthmatters.me/userfiles/file/sabor.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16085d9917af1a---netarosujubuguxuruxeje.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a44516de1---10710376107.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bb697540f2a---pefesoxitukimaf.pdfIn PDF document text
    • https://rhodium.vn/uploads/news_file/wutemudubagobodogakisoki.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/xakabuvejezikixo.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607277157f9aa---40475772615.pdfIn PDF document text
    • https://esportenerd.com/app/webroot/ckfinder/userfiles/files/zuvimasozek.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/pasibokugigagudemanule.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/popixugokip.pdfIn PDF document text
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/9f72aae8e63a012bab1c7a790b740d3e/podetewor.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/5cc59c1f7539747dfe2c4952c6c37b8f/65544480304.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160825d0fdfe99---zifoxodozoj.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081b385eca55---83596242704.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082cb92a2ec6---56349819865.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/o2amfb3mo7novj12p4agi36hvg/82004689061.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16095fd328d18d---64138779925.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/37069150393.pdfIn PDF document text
    • http://jarosi.hu/files/file/93603791784.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160c974491b0b2---ronenewonuzanisuzoruziged.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=%D1%81%D0%BA%D0%B0%D1%87%D0%B0%D1%82%D1%8C+%D0%B8%D0%B3%D1%80%D1%83+clash+of+clans+%D0%BD%D0%B0+%D0%BA%D0%BE%D0%BC%D0%BF%D1%8C%D1%8E%D1%82%D0%B5%D1%80+windows+7PDF link annotation
    • 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_off0000d9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1EB 11980 bytes
SHA-256: db26dd001e6a01cb80382f90d19b681675e2a522f776055b4c8f6b925884ceba
font_02_sfnt_off00010d88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D88 21548 bytes
SHA-256: bc3216b66226bae22e50ee071d5f007a082ad3c28c05c20fba179dd400cd93c0