Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7bfab9a38312872…

MALICIOUS

PDF

83.3 KB Created: 2021-09-08 23:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fa707f9eeaf88c0a1ee3cd88fd64347d SHA-1: 3a5db1b92751237d98d29f00f47d2c57cf5e87df SHA-256: a7bfab9a3831287299af9aff8735c4d4b741de101535c88b2ee4fb655aebffca
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external URIs and link farm heuristics, indicating it's designed to redirect users to external sites. Several URLs point to compromised WordPress upload directories, suggesting a tactic to host or distribute malicious files. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://pistant.ru/uplcv?utm_term=iphone+7+screen+lock+bypass PDF link annotation
    • https://zakarpattya-tour.com/upload/lajejuf.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/83078775223.pdfIn PDF document text
    • http://agilesolutions.in/uploads/98072903611.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f844268d1c---fominusagufaxutodelurifir.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/gixelotamajutumog.pdfIn PDF document text
    • http://ibrahimalsada.com/pics/file/tuzuwetisinipovir.pdfIn PDF document text
    • https://macauroommate.com/ckfinder/userfiles/files/tobajavawivuri.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/42925598264.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b10391950---gurajenavewuxezuverapejes.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/mezomus.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/51263641282.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12102391549.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/72215135485.pdfIn PDF document text
    • http://ontis.sk/editor_uploads/system/files/52803731874.pdfIn PDF document text
    • http://meghdoothsuzuki.com/uploads/10975806117.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/foziwuwapuzitasota.pdfIn PDF document text
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/wodasenuzi.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16134566281684---kuzebenigapebewulatinewaj.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613319d6dc5f6---ridawugofipaxizemuzoxiwu.pdfIn PDF document text
    • http://boldogelet.hu/media/71359884047.pdfIn PDF document text
    • https://duongthuy.net/userfiles/file/zubivepaxezivukopemeben.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/9d3237e37c9863d968f3f36fb76ec28d/79430090007.pdfIn PDF document text
    • https://everestart.com/images/stories/file/pugurupibugufos.pdfIn PDF document text
    • https://tatvan.in/userfiles/file/sululopuvabuwen.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/zuvemitufilo.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_off0000defd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEFD 18580 bytes
SHA-256: bcf494f634aff27b8f78292cab4c3a0509a467c0e52dbb4b86e701ad11311e66
font_01_sfnt_off00010f28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F28 10628 bytes
SHA-256: d777a32e4b865b7203a5ac619376b2476407822c78e1e8c3fc285866984f64cd
font_02_sfnt_off0001274a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1274A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1