Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4d50bfa092884d0…

MALICIOUS

PDF

81.6 KB Created: 2021-09-18 08:30:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0720407ae429cfd5f0b4dc4220eebf24 SHA-1: 7212ac5660528638f18d4c48c713ea0bca0e5b1d SHA-256: e4d50bfa092884d0e3f8751a0be04b8ceb45684ca54dffa9b480ba814a56e252
164 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to compromised CMS uploads and disposable hosting. The embedded JavaScript likely facilitates the redirection to external URLs, which are numerous and varied, suggesting an attempt to distribute further payloads or conduct phishing. The presence of multiple compromised or disposable domains indicates a pattern of evading detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=ppsspp+resident+evil+5
    • https://self-storage.sg/images/uploadedimages/file/fawazisi.pdf
    • http://tele-klass.ru/i/upload/files/25563242138.pdf
    • http://seidels-mineralienwelt.de/images/uploaded/file/3936483184.pdf
    • http://bulk-supplies.com/userfiles/file/jufexosama.pdf
    • http://ossokahve.com/upload/file/43802638681.pdf
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/77559571529.pdf
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/75338465761.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a80c5a490d---gukoxi.pdf
    • http://clear-es.net/yamituki-n/uploads/files/1828787386.pdf
    • http://www.patriarca-batiment.com/ressource/site-image/files/15478783828.pdf
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/nupenerowofisun.pdf
    • http://ibsdhc.hpds.work/ecdemo/web/js/ckfinder/files/files/80466623966.pdf
    • https://grupo-kayros.com/userfiles/file/71519745015.pdf
    • http://cancunday.com/travela/img/files/44228469252.pdf
    • http://panda-es.tokyo/yamituki-n/uploads/files/39328502336.pdf
    • http://simonide.org/userfiles/file/gomibogopafokudelosu.pdf
    • https://laundrybyconrads.com/nbloom/fckuploads/file/56032924909.pdf
    • http://nocleginaplus.pl/uploads/userfiles/files/91934499956.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136922248042---tavazidanos.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/127f37f4a04c1b6eec8c528825c7ab4f/jukamite.pdf
    • http://cardealer-space.com/js/upload/files/wakifobajasak.pdf
    • https://liantoong.com/archive/upload/files/lurisivakelupujo.pdf
    • https://clubberia.com/js/ckfinder/userfiles/files/98429803717.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/pspijftahcjkr91i9e24uqrr07/33799999108.pdf
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/bipumexam.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/67586d4af56974d7277754935e7a3fa9/15747166875.pdf
    • http://dedanskecasinoer.dk/userfiles/file/65657297587.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_off0000d378.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD378 16792 bytes
font_01_sfnt_off0000eb8a.bin
210b81493465c099933db945daf1455fbff9e05dd1dcb40a6d61cb40cc14c0c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB8A 20188 bytes
font_02_sfnt_off0001215f.bin
4bab45443bc11fbc409381757022f8a370f86df9fbe08d7e439e0ce0c177a044
pdf-font-stream PDF embedded font (sfnt) at offset 0x1215F 10304 bytes