Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcffd54c9e73c0cf…

MALICIOUS

PDF

73.9 KB Created: 2021-09-01 11:34:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d58a6f650f5fe018cb0564ac47897200 SHA-1: 40d23ba88b014c50880fc170e8708edd456f9575 SHA-256: fcffd54c9e73c0cf7198950ccc30dcb4a9a8ce028d2d189570243948685811f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous external URIs and link farms hosted on compromised CMS uploads, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://coretry.ru/uplcv?utm_term=can+a+banana+be+too+ripe+for+banana+bread PDF link annotation
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/1a39fd72cf467f962a9dc250eb0e87d3/povirapagadur.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/eprggvt6o8odhpsgn7vm5sqese/bimikogijaforamimegexota.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/29489608128.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3ad880a3d---jakejotopujeg.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/98413180881.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/divaw.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/dukadagakosinidowixuzawe.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/d6984d4bd026522c1af8ca5bf18abf6e/titunigufebab.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/mutire.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/53nm4qs26v9io9bd6qkjouu6ql/difelazawedirupo.pdfIn PDF document text
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/diribuzelafakibudu.pdfIn PDF document text
    • https://valergences.fr/userfiles/file/mimigabojuzegamigob.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/vomodutav.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/15odood9tcrrib5vm1aiito34c/9463015483.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eed5989dcc---nenoxe.pdfIn PDF document text
    • https://stbenedikt.ch/userfiles/files/vasomosudigobagit.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd449ebc037---2216290373.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608155c982216---35225028122.pdfIn PDF document text
    • http://yaeram.com/userData/board/file/wijesegamelovej.pdfIn PDF document text
    • https://viessmannboilers.ca/fck_upload/file/65353082206.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/2938990876.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c39833195---vekorebudukibolas.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16083d8b643020---gurisikibinatini.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/6lul35a4sha6it5uqkk547vjs3/55166644802.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_off0000c251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC251 15764 bytes
SHA-256: b3f4b3c87f79c68d12bc7291cb550e66d8282023f3ce412e7119feb812fea236
font_01_sfnt_off0000ea7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA7F 10448 bytes
SHA-256: b552e9d0c719edc7c60660d95819ed8af1fdc2ae76008bd9d3722c39266c67c3
font_02_sfnt_off00010222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10222 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1