Malicious PDF — malware analysis report

Static analysis result for SHA-256 28df72065141946d…

MALICIOUS

PDF

93.5 KB Created: 2021-06-27 01:01:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 964c68c1c75fdac41b3d3ce02ea489ed SHA-1: 9c0d917a025b7ff810205371a35bfbed89c93ea8 SHA-256: 28df72065141946da220e4d3af295a95246fc381c55e4abaf29da8585d89c4e9
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites and disposable hosting domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://lifecareproduct.in/ckfinder/userfiles/files/kafemiluzerujisutubogop.pdf In PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/44280236156.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c6646350b4f---30879687230.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/0ccee98769c7357dba7f4d29d04e4d48/wavamurozixezexotudatig.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/dcd1de6a3ef071888dd29a531de457c4/655163288.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/l3dffvnhipl60aqsucu8c0e7bf/52933616924.pdfIn PDF document text
    • http://hysansam.com/fckeditor/userfiles/image/76580190369.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160a17d9e485b3---kuxadinekof.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160915a5ec153e---20581959114.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/d2da46eeb522b0d07f4a865736bd3e23/nonalufusoto.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/61221579776.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/mcl9mlq5lbuho9vdi23hm9tupb/gibiruxa.pdfIn PDF document text
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/36568f4c94cc768650cf91744e56cd9e/81580295810.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/99162265243.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160abda61cd624---neferora.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a73f0602c7---44738064557.pdfIn PDF document text
    • http://klefmarken.se/upload/file/fupusutibenorefoxatalupir.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210605070930.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acb2afdbb1d---retogipuvefanezeb.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad946d3cd4c---matuvowatazuze.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/c216236bc615824c4a0c884689a04010/34531930276.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/681fe85dfcb5e4f32df38ba7680944f4/tanulisibedugekiwar.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac117a1e8e2---venorojotawowinujanesar.pdfIn PDF document text
    • http://guilfordvikingsclassof81.com/clients/4/47/479b0a304b4cdce99dfe3eda73a59016/File/fatujibatafudaj.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/satabi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=stephen+covey+quotes+begin+with+the+end+in+mindPDF 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_off000108c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000120d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D8 16948 bytes
SHA-256: 1931725c1c31a5317bce520f0207e163accce09fa762c5c614f7b2b15e2ddd97
font_02_sfnt_off00014c9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C9E 11380 bytes
SHA-256: ca665fd7f4a43e957de9c5b93c7b49c38c7ce6ca4e44e1b3c55226d424e67a44