Malicious PDF — malware analysis report

Static analysis result for SHA-256 6391e1dc646e4d4f…

MALICIOUS

PDF

84.6 KB Created: 2021-08-03 23:31:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 42789e6a44d76e8df1b98f2c93728183 SHA-1: 37792e5b2d1e499055ad3ced087f369b8a249468 SHA-256: 6391e1dc646e4d4f6b48e743ad4d719580ff6a490c36da1862bc397590116853
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs that point to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users to potentially harmful content. The primary attack pattern involves luring users through these links, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://easttbirds88.com/clients/d/d7/d767393c090093bf18db16876c07b5c3/File/68850129185.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/95its95qrfciknbbonkm7sc6lq/kixazuzik.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//zopeda.pdf
    • http://cameralehiep.com/hinhanh_fckeditor/file/3879897198.pdf
    • http://ourjamesfamilyhistory.com/clients/1/14/146a9f92d0a296c7c29e793db058bb30/File/sirovuxanupuxaletem.pdf
    • https://cafepiolho.com/uploads/assets/gutunikomofefegedoxug.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/6a9a684f9770b68d1b6362c4d026e7b1/65390686658.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/1mr2a9n2r8iul1tn9hd2d7mcl0/wurexixavikat.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c026cebaddb---fudigutafedodiz.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/d1e89f0f477654de8fdad2cc806dd2cf/renebevizavolat.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/c14d716ea7c9b1143d73e10f98a97f78/zanibakijidekok.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/0afb4e485dad88ac5fb45815ae3fa379/fokabir.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088b8433ce63---1290665083.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c38ed0d5cea---tizusazited.pdf
    • https://fo-prefectures.com/pages/files/gutajukuzoxik.pdf
    • https://cafesca.mx/ckfinder/userfiles/files/89888945835.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/f1cd3b237f66119a171c8ce2467a6be0/31342744453.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079dcc838d69---38085307488.pdf
    • https://tdsns.ru/userfiles/file/fenovon.pdf
    • http://www.halpellet.hu/userfiles/files/gebitiwulaluredesug.pdf
    • http://scarpatti.com/files/gupisorubikivitaro.pdf
    • https://aadhaarretail.com/administrator/imagetemp/file/fiwusexosubejalorivokago.pdf
    • https://bliznacite.com/files/nevogitotisedufi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=t%E1%BA%A3i+theme+powerpoint+%C4%91%E1%BA%B9p+free
    • 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_off0000dc5d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5D 16792 bytes
font_01_sfnt_off0000f46f.bin
17f5b9cde38e3baf9701fd81f08d352a7ba11a427f3f9adc0da95453b5dfa6ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xF46F 27588 bytes
font_02_sfnt_off00012974.bin
10fa9d070e1a700f473f4d5dc57dbe09974a11d12732fe8b7e1f85b37627a09b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12974 10868 bytes