Malicious PDF — malware analysis report

Static analysis result for SHA-256 856eca8edc65ee53…

MALICIOUS

PDF

76.4 KB Created: 2021-06-05 16:46:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9d4bbd76814042e3eb19325d012c5ef4 SHA-1: 65e838693e174dcdcb7e207c6649534c8a4cc496 SHA-256: 856eca8edc65ee53a75159e5d6fee1c19f06b202453c6bc99c7ac549dc4d41a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged as malicious by multiple heuristics and an ML classifier. It contains numerous links pointing to various domains, many of which appear to be compromised WordPress sites used for hosting malicious PDFs. The presence of 'utm_term' parameters suggests an attempt to track user engagement with these links, characteristic of phishing or SEO manipulation campaigns.

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://smidgel.ru/uplcv?utm_term=class+rank+reporting+quintile PDF link annotation
    • http://ccforum.kr/uploads/file/1622017896.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/o45h1o94rle6ig6bb4r3a272q2/tidiveroj.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/q42ih0amp4hkpvk6d1nbfagr24/wexigalazi.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2934b970d---fegabubanip.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160764afe7839b---60986689538.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/ijjgeq8eh4tlphuj1b9mdqrtt5/kitevuwutugagux.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/b245f5ccc89da07aba38dcf00e20d4f3/55591083345.pdfIn PDF document text
    • https://blindnow.com/userfiles/file/72264494328.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/38513725458.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/b222565e0d9d4ca29c96f583e63f24cb/39094931705.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1607f35e91567f---lijuw.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607208c9f254c---19082255050.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79989e6042---6382304346.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/jukssmgm2775qdurdcco7ruub4/vilapujit.pdfIn PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/7iemassrfed3v9nt02sqelqidv/xedogaxow.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FD 5080 bytes
SHA-256: 46e6dc5d15e7bd380bc49305024167951216dde87ce0757b3ab2f1889d6c1d5e
font_01_sfnt_off0000f647.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF647 1800 bytes
SHA-256: 51ebeec29509b87aa858d500e37ac8853184703d07d1f913ce36d8e1dc7764c0
font_02_sfnt_off0000fed5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED5 10868 bytes
SHA-256: 8ae5a83c4f2677f2bd70fb0183bb3b915f2715d749d1fb0cd4324bcef5e6cce1