Malicious PDF — malware analysis report

Static analysis result for SHA-256 af4875da259dfb41…

MALICIOUS

PDF

78.2 KB Created: 2021-06-10 06:06:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: cdf26c31cd1458e8fcfc34a87629d7dc SHA-1: 6dbdbd5e9ff242c15a490c78dbe19f9038f6fbcf SHA-256: af4875da259dfb4137d413e78c234ff002b53136f17ddb2eb50d493f774dd2e7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting domains, suggesting a phishing or malware distribution campaign. The ML classifier output of 0.999760 further supports the malicious classification.

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://crysiq.ru/uplcv?utm_term=degree+of+comparison+exercises+for+class+9 PDF link annotation
    • http://www.prieteniitehnicii.ro/documente/file/vomej.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ae3c9f335---86524446377.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54415e1074---82534457730.pdfIn PDF document text
    • http://lhs60to70.com/clients/3/32/32806278e47d7e4d905c37b1d6ebf04a/File/tiwowisotibezume.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/jo61t72gqgk8i1pbgvvtvkv347/76284326668.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/suxeligasorijip.pdfIn PDF document text
    • https://101doctor.com/uploads/ckfiles/files/60b056991539f.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5b463c7ea---92172209396.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6d1ee86a2---52058098183.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/vhmtakn7k92e1c43m5m0uevcd5/wuruvoxiwe.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/68cd680896f0bd01c0b40d02ddaf26fe/jaxixabizutaxomuru.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a1bea7e4cd3---gitoradodopa.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/emonncr5fjqru7td401kgiu906/2784439027.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609d96aa2732c---95470449552.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/tf98dsrpik5vfqfm8rere8nmj3/2106344977.pdfIn PDF document text
    • https://www.haievent.com/wp-content/plugins/super-forms/uploads/php/files/3suu0ninjb6vv05j1kapfkuidp/75668608660.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/4da90955d7949f33e47e324e2dea4583/sulubosubirupo.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_off0000f3e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E5 5556 bytes
SHA-256: d76a1f839f0c1aa5ae81accdce765602f4359162ba73a99998b0d3e204ed0b24
font_01_sfnt_off000106c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C9 10740 bytes
SHA-256: f86db72671dc7a728d3af77a25bce95f4064d97018e36690f145088c7be82fc5