Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4dc86165b23d1b6…

MALICIOUS

PDF

76.4 KB Created: 2021-09-14 10:03:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a3eda88139b8523d5302c606467041ec SHA-1: 94e25bb6a4b4007912ac8327b4df32d8f3127a56 SHA-256: c4dc86165b23d1b672522492067609208ccf72ce992806e59f7215480aa00a18
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document's structure and embedded links are designed to lure users to external, potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://www.agencesramos.com/ckfinder/userfiles/files/zewun.pdf In PDF document text
    • https://marbletreasures.com/uploads/image/files/mifotenewogud.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/6086943348.pdfIn PDF document text
    • http://diadiemvui.com/upload/files/jibakufi.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee5e7b9ae5---tolipawumawi.pdfIn PDF document text
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dafupubidudulope.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/c94e8e6a288b02c018dc41e3fc2fca97/mipoguraxokirokukoponom.pdfIn PDF document text
    • http://cathugo.de/res/wysiwyg/file/44442388148.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/6019563445.pdfIn PDF document text
    • http://bakoca.hu/files/file/57602591421.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613499c00748e---tajiradodewedu.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/59176742932.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/87961211986.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/kuferezifimefo.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/4a3cff25396c4281b4a92a351f181623/tutajozabusi.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/93281450191.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/salada.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/87879178625.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/lotumawabajamululiled.pdfIn PDF document text
    • http://haihengpharm.com/upload/files/11006008622.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=3+letter+words+with+vPDF 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_off0000c6ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6AE 17844 bytes
SHA-256: 34ed1c37a8ff5401e14e9e5c43cc17aeede06f647e4429b4d1a4066acd290626
font_01_sfnt_off0000f4c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C7 10308 bytes
SHA-256: dd146447153d5687c4e359c1d4057d9783ee68634b67b9c7a4969118b2f6a38c
font_02_sfnt_off00010c2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1