Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3c67087342a7ac3…

MALICIOUS

PDF

88.8 KB Created: 2021-09-12 15:23:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 77ab8a68f846be3687551f341fefc00f SHA-1: 4e4a4b62d27c228ca87295e75421d50fd363815e SHA-256: e3c67087342a7ac3ee5b6891497f2836a5bbdc99a2456dd4c4b5f9b70f80846e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a link farm with numerous URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://vivo-mebel.ru/upload/file/pazukebusatasufe.pdf In PDF document text
    • http://lehnerkom.de/images/uploaded/file/losetudesugu.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/48997184252.pdfIn PDF document text
    • https://makanbanyak.net/contents/files/bexopukapisolap.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/95397966f6811e8f9e189d4d4a7617a0/5138817242.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/35802110479.pdfIn PDF document text
    • http://www.workbythai.com/admin/assets/images/9854572417.pdfIn PDF document text
    • http://zhuoxinlaw.com/userfiles/file/20210910154424_707851149.pdfIn PDF document text
    • http://lawngo.net/fckfiles/6736110657.pdfIn PDF document text
    • http://vititanon.com/user_img/files/sopiwit.pdfIn PDF document text
    • http://haustechnik-hagenauer.at/20926803779.pdfIn PDF document text
    • https://lacgl.org/upload/editor/file/lumedoja.pdfIn PDF document text
    • http://hlqh.net/userfiles/file/20210906230112_247615173.pdfIn PDF document text
    • http://ekmeta.lt/failai/file/bapudikurojupobu.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/202193199312110.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210901143051.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/11931208466.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/f8a1d031b121c1da6dd2ef16bd11bb5c/waxizid.pdfIn PDF document text
    • http://adas-muko.pl/photo/file/5370969329.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/mosavewujomiw.pdfIn PDF document text
    • https://loyallcanada.ca/editor_files/file/75972762942.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/7baa3bv3e7fl03i71av46plie0/tumovu.pdfIn PDF document text
    • https://rafautama.com/uploads/file/rixejuvopox.pdfIn PDF document text
    • http://sungder.com/upload/desemu.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/tenawuno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=wifi+file+transfer+for+pcPDF 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_off0000f61f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61F 10464 bytes
SHA-256: c1b0c8a129151a8353f5cb0e0d791452533d9e7f03da01bfa90f99150f985147
font_01_sfnt_off00010e06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E06 18300 bytes
SHA-256: 8b89f10d6f98a2eee80de0f736db9337f74f347df857671634b7238a7beeda21
font_02_sfnt_off00013d84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D84 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1