Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf7ea815c2b6e44e…

MALICIOUS

PDF

80.2 KB Created: 2021-09-22 18:30:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7facd475b7668e47e6b0c91c46e01de6 SHA-1: c215ce444b6a1bed316b7cce370804bea6be4fa1 SHA-256: cf7ea815c2b6e44e0ee4c3586d97d88087028beaae6640d30297b304dbfb3b8a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to disposable domains and appear to be part of a link farm, suggesting a phishing or redirection scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a low-quality, potentially malicious link distribution. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://z-i-f.ru/userfiles/file/tasomulo.pdf In PDF document text
    • http://studiotecniconuti.it/userfiles/files/zuzagevubesisenol.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/66245945915.pdfIn PDF document text
    • https://wangwangcamp.com/uploads/files/202109011559008740.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149895820199---70664621824.pdfIn PDF document text
    • https://minjar.mebel18.com/uploads/files/43165840075.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/47881319376.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/55908221798.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/74304281999.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021092202383273499.pdfIn PDF document text
    • https://artedelvalle.cl/gal/files/file/bajilevadosabakani.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/ramepusu.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/23748850634.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/rosirud.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/75386688356.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/28200434547.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/tolevosivapalamuwuv.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/45030473054.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/2240501.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/wuzimutonokifutawin.pdfIn PDF document text
    • http://przyrodnik-kujawy.eu/userfiles/file/komutizewebadojarugisogex.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/14827513352.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613246147a393---66568819452.pdfIn PDF document text
    • https://cafesca.org/ckfinder/userfiles/files/64646434480.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=rooted+and+unrooted+devicePDF 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_off0000d3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3AE 18764 bytes
SHA-256: 75766e36e923b9d2bbedcb456d2ed0990c80b6a3517de7ae997b5dada21e518a
font_01_sfnt_off000103c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C9 10360 bytes
SHA-256: 568963b869636e80ed753d5d12590cfdcf798789a6d738499ac827dafb2d7ab3
font_02_sfnt_off00011b5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B5B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1