Malicious PDF — malware analysis report

Static analysis result for SHA-256 c304cc2daff89b18…

MALICIOUS

PDF

84.4 KB Created: 2021-09-22 23:18:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 53fb5f46ef2e5d0d7d7747111a039715 SHA-1: b46dbb4df140a1373d106d6b2ae02461a5f79e29 SHA-256: c304cc2daff89b18a667d9a3a6d8363c1c8fb3f05bd739e5df932b625f61ec36
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS uploads or disposable hosting. These links likely serve as lures for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • 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 http://nacyc.jp/Upload/file/43658286064.pdf In PDF document text
    • http://9262895.ru/ckfinder/userfiles/files/43528306730.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/17062251408.pdfIn PDF document text
    • https://33mobility.net/uploads/files/23323191219.pdfIn PDF document text
    • http://yoron.net/up/files/jabefetomigotowitebitew.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16147fcd2b0a5d---62266674399.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/jogurikewa.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/55300863827.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/xikeroribikonepokaku.pdfIn PDF document text
    • https://conexus-study-abroad-travel.com/ckfinder/userfiles/file/piwedimix.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb9f0791e5---govibubili.pdfIn PDF document text
    • http://nofatrans-int.com/userfiles/file/jomoxedekovikadexapaxe.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16141659f78626---35137209526.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/1k7qfeoga0dm60u9lua90gmdpv/giveje.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/wuxodiki.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613450fc06533---jiwitizonalofikig.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/35204489377.pdfIn PDF document text
    • http://cjcounsel.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/67023372971.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210918_161623.pdfIn PDF document text
    • https://vicotelecom.vn/static/source/images/file/53197425029.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/lijitosofowajelapunizato.pdfIn PDF document text
    • https://sibconsulting.com/contents/files/43536195894.pdfIn PDF document text
    • http://administratieindex.nl/images/uploads/89345568763.pdfIn PDF document text
    • https://dtd.com.pk/ckfinder/userfiles/files/nuzab.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/68ro11cgdpsf4ef842ms7aba82/rapevatarikal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=pideme+lo+que+quieras+5+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e00a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00A 10836 bytes
SHA-256: 769b33805c2070ee794224ee83a201dfa7593eba9682ad189c0217970722afad
font_01_sfnt_off0000f8da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110EC 20284 bytes
SHA-256: 7f70993be34da9020c644571a585586fa64108e3c52a64a53d96102271bfc902