Malicious PDF — malware analysis report

Static analysis result for SHA-256 41655a30d416e8f7…

MALICIOUS

PDF

72.3 KB Created: 2021-06-11 19:54:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 465bdf69901e5559aaa370afb63d7d58 SHA-1: bf6ea5bb53d8d7b6ddbe59e38b1f986f5a193850 SHA-256: 41655a30d416e8f7331a27dfa09dee145b5e561058d0770a68ea320a86f5d8e6
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains multiple links to external URLs, many hosted on compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of 'utm_term=fs+18+download+hack' in one of the URLs indicates a lure related to software downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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=fs+18+download+hack PDF link annotation
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16083889d61f61---31150982817.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ffbab571f---37793184751.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c2e9649451a---62505954380.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840ff20d17c---7574621232.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a676081620a---detimofilijofubafifumipim.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/lsg3d87oqf93b1c6l0tof834mk/reganakasabelebop.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/68017160250.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/c7ufbqigsh4qnscsa712gv7d5q/85622917326.pdfIn PDF document text
    • https://stopserv.ru/files/file/zesikosuluritepag.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607155abd7e69---25079895144.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54065719a8---63264959628.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/fobediduzozonizazete.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/352aa620fd08f03a3a119c602185476a/48628513939.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/xevekotazizemisopizoxir.pdfIn PDF document text
    • http://massageindex.nl/images/uploads/64725045568.pdfIn PDF document text
    • http://webursitet.org/Files/file/25235469863.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_off0000ddd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD9 5288 bytes
SHA-256: 49c3de4d1ab1a602e08c65194849fcfa0c25dc86c9dfee965b8054e837e42554
font_01_sfnt_off0000eff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF1 10756 bytes
SHA-256: d36ed9fd9c86878786c7336e94a46d1d110cc2b0316ffb0726a8117bbda4eaba