Malicious PDF — malware analysis report

Static analysis result for SHA-256 08660b2377f86af4…

MALICIOUS

PDF

77.2 KB Created: 2021-06-13 19:28:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: aa8bdf097a29c368a9f2ff6f65e00f2a SHA-1: e7809e98711e7f889b9e5797a6756f696f133f9e SHA-256: 08660b2377f86af4a49e625a62dfb2aece7e47eba60500e9213dc56b4e389186
156 Risk Score

Malware Insights

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

The PDF contains multiple links to external websites, some hosted on compromised CMS platforms, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of numerous URLs points towards a link farm designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://irlanc.ru/uplcv?utm_term=mcq+lipid+metabolism+pdf PDF link annotation
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/0ac21bf2989897164ae55be5c987c35c/zijoxupuvanofugoxuxafufen.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160812da3f1d86---zudawevitotatuno.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c01909fabc---vojiwezoda.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/km9cujvl6stlvtpp8rd3o3lrod/95739070732.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160701668538f8---34393839408.pdfIn PDF document text
    • http://ferrogep99.hu/static/media/file/fexefovikukenol.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29e19acf21---85518359054.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b509ced8f---wamupobevupatolokenoburul.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16080c08972b1c---11168679897.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607db3a274f06---13116581086.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a3adb10579f---rolaxupunese.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/20682850095.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16087235a7c18b---fogesimetufimebaxixavini.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/34cda3fe098ee3958b6259c8642b4fba/lipefefurepagimugelipelo.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160890a030df1d---31516264786.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160875ab25949a---44859583436.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE39 5476 bytes
SHA-256: 6589c483d9d29246e79cf46fc5a37cf51d548754d8561b174b84634e9b10bdb5
font_01_sfnt_off000100cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CC 10972 bytes
SHA-256: a02466bf75669dbdcabf5f16fcd42f16db10502987d36760f1d2044b812e1e9e