Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd39874fa926b261…

MALICIOUS

PDF

76.8 KB Created: 2021-07-03 19:25:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 187e3f247bfe35cb6fc43dde4ed23009 SHA-1: 5007c72d34fef58f6cc1016f3d3fc2e596ee9f1c SHA-256: dd39874fa926b26173e5f787d76036f87068f8576ddee81e0205758ec7e6fa05
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories. These links likely serve as lures to phishing sites or malware downloaders, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df666f0f001---zitidizelamowofuxixax.pdf In PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/e9b927cbd170c726fcd5254966949bf6/tazapawepage.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb506381a6d---bujogubaj.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/o443ok4a8rgqg5bnb0fkdjavin/4483979740.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/gusotegupunomarexaluvi.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/80518067573.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/2040fa3f9bfd77830fbcbc7111612400/lelone.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/zajed.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/58640718441.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/10pti53qbl2lscc3i8hl2po581/likelekuvip.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/98211374031.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/tavudalamibak.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608334cd062cf---20389749393.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/07f61c178ed99a575c6f7198b7e05c22/77754703655.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/poxigaramomunenefo.pdfIn PDF document text
    • http://salinahighschool1968.com/clients/3/33/33fcb9b832a528c934b1ac42c6b88a99/File/80414156004.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b499cd2addc---57398522117.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1993d784f1---67192377913.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085368da7afe---64460950389.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/tivemazesaruwakijes.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/83150177976.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/95c866b041dc23bfc695dcaa5ec14f05/5162278902.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/tupilefazunapugu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=little+shop+of+horrors+pianoPDF 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_off0000ca62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA62 16912 bytes
SHA-256: a9fcd321bc14673c8db696399631dc4ce73ca2a82246bcee8e30034449140829
font_01_sfnt_off0000f65b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E72 10412 bytes
SHA-256: 9bd0bcbcd8c9dade696cc982594f1a98000b9ae23a1ef5f4941020f9a1a9568d