Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b3e9ca841c6977…

MALICIOUS

PDF

88.2 KB Created: 2021-07-05 00:18:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c2326035311ab2b8fd20d3dec3a55fb SHA-1: 02427c33456eac41c8117566c945e9fa056b7bd6 SHA-256: f8b3e9ca841c69770baebc05400c9e53b937d825a27fd58dfdd8a6e06a532833
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a link farm used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://atl-50.com/files/file/tokatovepe.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e16f2385e---96399744006.pdf
    • https://derechosenred.org/aym_image/files/nuvujidapu.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16073b472b0ed5---nidomawopisosukidutitisa.pdf
    • https://svetplus.com/userfiles/files/14320687396.pdf
    • http://bbpcosmetics.com/admin/upFiles/2021-5/file/56922214365.pdf
    • http://osoboebludo.com/ckfinder/userfiles/files/vupitirod.pdf
    • https://yssnewlessons.org/UserFilesTwo/file/sofeg.pdf
    • http://airsoft1.ro/files/file/52762943879.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/5dcb5f5322bc5f4db2ad9327824bbf09/91330282271.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/c4a6bf6c8a4f8d76d48613360e0b6066/vowot.pdf
    • http://asesorgubernamental.com/images/file/12241295966.pdf
    • http://camwater.org/media/files/23640467422.pdf
    • http://alexandercdg.com/clients/36029/File/70630332961.pdf
    • http://fipjp.com/userfiles/file/99342000095.pdf
    • http://lroundup.com/clients/d/d7/d7466da0ad72d96b64793f89c518a0d9/File/pefamevaporipafukupanuzu.pdf
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/e0f22a98d1c2585bdaf2297e3345255b/68204983274.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b9eeb0bb866---zobawusumaviroripet.pdf
    • http://mppscstudy.com/admin/usercontent/file/fuvulutamurade.pdf
    • http://oreade-breche.fr/userfiles/file/16609531631.pdf
    • https://gamaconsultores.cl/upload/file/jerefakaxitunuxi.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/b7a55665eb3a063a463ab3a7322d8c31/jidojasev.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160827ffb31b12---buwutofowodopinon.pdf
    • http://loscogliodifavignana.it/userfiles/files/maxusalufowuxijorojew.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ed5bb07c1---421061773.pdf
    • http://beloezoloto.ru/userfiles/file/10748162353.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=very+light+brown+period
    • 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_off0000f810.bin
17c451ea2d47f0c80d5ea02aa34c67a0f563e0f63f34f9b31e51bb0a32b1e07e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF810 16756 bytes
font_01_sfnt_off00012369.bin
ff7b8cb5da086611b1cd9d49075f34bd782f0e05bd8e18d4733ef41cf3b0e28d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12369 10648 bytes
font_02_sfnt_off00013b49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B49 16792 bytes