Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f31021ebe811a79…

MALICIOUS

PDF

85.6 KB Created: 2021-07-01 11:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 13bff853820e4db0470473263ec7dd2c SHA-1: fec03b3a097f8609fdf53651e67b996547fcf437 SHA-256: 5f31021ebe811a7987f9a64c95e25750581abd5af176c8c0656ab47161462c74
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, many hosted on compromised CMS platforms or disposable domains. The presence of embedded URLs and the nature of the link farm suggest the document is designed to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://synerhu.ru/uplcv?utm_term=red+crucifix+meaning PDF link annotation
    • http://wongkungfu.ca/clients/f/f5/f5c316b966f29b3192b3e9e3c5714b3c/File/80423000006.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/13898789347.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606e9a58139a5---pipixosijutumoza.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///2021621141179009.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/5c1fdc1ee4ac2cf68a2ddcf4e4b2b021/vitufogotupuforojawofir.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/81461490627.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/kgsqbocfst3gh0jmp8c9u8e92n/gujimetulatorunamezepazib.pdfIn PDF document text
    • http://aweibel.com/Photo/file/darijuxelivisikizatorek.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ec56383e4---83981239008.pdfIn PDF document text
    • http://eksan-ltd.com/userfiles/file/73375743273.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/v2nprg1f9ph4os8o9ope72g0rt/45574085722.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/jusejad.pdfIn PDF document text
    • http://softtox.com/new/userfiles/file/tepobopapotumosek.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b20074de82c---60275433418.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/garewixa.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b20442ad96---2097594839.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078596f1abd5---lexebi.pdfIn PDF document text
    • http://notarbrazda.cz/userfiles/file/83952933646.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/20066476733.pdfIn PDF document text
    • http://unityproductions.com/upload/files/naxiwunalupomo.pdfIn PDF document text
    • http://feuerwehr-mittenwalde.de/mediathek/files/19414199986.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607008395169e---42732997441.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/xadugofewumivitofarona.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/jenupifonaxo.pdfIn PDF document text
    • http://menloathertonhigh1980.com/clients/6/6f/6f83464fe0b13873896cace574d4baa5/File/tajesaso.pdfIn PDF document text
    • https://divinesacredshakti.com/wp-content/plugins/super-forms/uploads/php/files/95dd34bf1c5823aec148fd65cbd228c6/45218552619.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_off0000ea5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA5F 17696 bytes
SHA-256: ac31d9bd30865b7fa30c7bed20f98a870cc04e2e002323bde1c177234b5246b5
font_01_sfnt_off00011902.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11902 10632 bytes
SHA-256: d01802708e9a1bb26020919508d7d6d8022b43bef027622a0f5adef800d3ed2a
font_02_sfnt_off00013113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13113 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1