Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a390ec98d7bd5f0…

MALICIOUS

PDF

87.4 KB Created: 2021-07-04 11:42:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 29e6f0469d5293adbf834f58660f0f7b SHA-1: 5dde5b0df4583bf903c0e1f15d2d771806406748 SHA-256: 8a390ec98d7bd5f09748ea9b38e9ff45d2612c246bb61b9ae87c75faaeaf550b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs that point to compromised websites and disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on compromised CMS uploads and disposable hosting. The primary purpose appears to be directing users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://smidgel.ru/uplcv?utm_term=country+song+about+grandma+dying
    • http://paynechapelduquesne.org/clients/9/9b/9b910c66cef3ae2d1bb1fd5804160a19/File/10265040876.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/4rarn4i3j1vabf4sajc18q1517/92483616906.pdf
    • https://grupahatak.pl/admin/_fck_files/file/97204676775.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160786f2773ffa---58221630362.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077a935aecfd---25661858313.pdf
    • https://tskrea.com/userfiles/file/99089245825.pdf
    • http://gvs-russia.ru/admin/ckfinder/userfiles/files/3938919538.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/0d8iu6r7o4mavm05h6u7o3phjn/2982949497.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b9d892388---pivofukivufowatijagakibu.pdf
    • http://www.monts.sk/upload_images/file/82866342508.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6431c8719---79098420220.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/br7f7hio6oq73sc37imcvph7o2/xapilog.pdf
    • https://liniagdanskzydowo.pl/files/72821520599.pdf
    • http://citra.cl/userfiles/file/pevukuzodajigem.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/6dd0fcd8cb6eb50737692e3bac9d088c/rupevifawozuba.pdf
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/e57d1900ea83de3a567ce50458ced9ee/tepuwati.pdf
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb15b7f139---senazaluvuv.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ae257507e42d78dc47ac90cb66f985f8/maruferizul.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/f623dddf6561b89f30e5688f41265a4f/59013978480.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/edc3e0137c923fca6b8dbd9b90dd2f2f/85907717090.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/c1a6aa808364746c3acebd9f3424e18f/70257838404.pdf
    • https://papersacksfactory.ae/images/bulk_images/files/nabenof.pdf
    • http://telekommarketing.com/firme_data/files/78794528974.pdf
    • 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_off0000f1ba.bin
5f7fe69098287ea1b186c6c21389b4947922c6a1139afb40a9db5c51af0badce
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BA 17060 bytes
font_01_sfnt_off00011e21.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E21 16792 bytes
font_02_sfnt_off00013638.bin
3b2e61f4df339d9b86e7a429e89f49244ba86b331c3cc33364cb1a846239554e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13638 10800 bytes