Malicious PDF — malware analysis report

Static analysis result for SHA-256 5dc035f5c2269adf…

MALICIOUS

PDF

74.5 KB Created: 2021-07-06 14:46:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: fd0d00acbd78bf515197d665ed5bd9f7 SHA-1: f590abb76b4d10beec5a74b6d2cd7e19192e167d SHA-256: 5dc035f5c2269adff44a3743bf216b9050b821d6cb1f857b23b16b6e10aa30e1
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of links pointing to compromised WordPress sites, many of which are configured to host user-uploaded content. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to obscure the true destination or to distribute traffic across multiple compromised hosts. No scripts were extracted, and the document body was heavily obfuscated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • 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://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/10c04d5e8c5eb4ca2f3fca98c682258b/27790731461.pdf In PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3e3685a46d---butenunutafegu.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609adafbe9b78---27557320159.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/ashclmsefo4hfnihgduoucknfv/rufuliwumuruvitom.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/1pc6aanu6qdhposqvm9dejbas5/kadibefotiduva.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2708ec9f68---wunegoparaxomimubus.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085c4a790ec4---92687793369.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/fujododadekimakowolotokev.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a8701eb0fb8---gipimijidobelodamubap.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0cac4d9f5---70905730691.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/46fba7f5bb22cd7dfab2dbe02c4c8580/kogiwuvuxabutewavaj.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e31679e556d---falotasot.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c285b2ab9---26688398141.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/45389245555.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/7725059218.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/2f2fa61bebc0a359c647d5b30b2655ec/501374666.pdfIn PDF document text
    • https://kasihpaham.com/contents//files/12314319474.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202105/file/pepirizasepebuzowubem.pdfIn PDF document text
    • http://yangpupark.com/uploadfile/files/57734221464.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160dbecc522046---fojurozo.pdfIn PDF document text
    • https://bataretak.com/img/files/file/xamanusereboragaruzifi.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/90104213090.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=live+commodity+indexPDF 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_off0000c147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC147 10296 bytes
SHA-256: 9db6c290423e87c5df903857011dc730def343b8f81ca2739ebf6898ce37b12a
font_01_sfnt_off0000d87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f08c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08C 16972 bytes
SHA-256: 1f8dfbcfe75099ac2601dd991f4fc951e98bb8ac1766cd955a7fe24969260350