Malicious PDF — malware analysis report

Static analysis result for SHA-256 41ef6e4d3dc3596a…

MALICIOUS

PDF

84.4 KB Created: 2021-09-16 19:03:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f8dcd86e01e9dd5e98508a7795621f81 SHA-1: 4d76cfa033d1726333fff2d4b6babbc15c0ef415 SHA-256: 41ef6e4d3dc3596a23a9c33f32bca52e0f59036f3e968ed7c432b5b8e38f6981
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm or disposable hosting. Heuristic analysis identified this as a link farm on disposable hosting, and ML classifiers and ClamAV strongly indicate malicious phishing content. The primary attack pattern involves luring users to external sites via malicious links within the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://www.salac.cz/ckfinder/userfiles/files/wivudomix.pdf In PDF document text
    • https://www.potravinyav21.cz/ckfinder/userfiles/files/74960691220.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/zorozovor.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/vawajuj.pdfIn PDF document text
    • http://rilta.net/userfiles/files/tuzimotemeviluseluvuk.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61565817552.pdfIn PDF document text
    • http://cheumst.com/upload/fckeditor/file/rowagubexegifazekof.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/14103632245.pdfIn PDF document text
    • https://camping-du-lac-dijon.com/userfiles/fichiers/99413646927.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/sunujemaxujevologes.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/8d76cd7f4e989a31772237e3596636ce/newuxonuji.pdfIn PDF document text
    • http://elrey-uslugi.ru/media/file/9167072268.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/81726980790.pdfIn PDF document text
    • https://deycaterers.com/ckfinder/userfiles/files/10188624313.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/29754539387.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/6692665311.pdfIn PDF document text
    • http://cargologicru.com/sadm_files/ziwowubekanevukodagaf.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/37625710754.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/64521668806.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/44405816805.pdfIn PDF document text
    • http://palazzodiaz.com/userfiles/files/99070866269.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/49528004313.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16141a7329ec32---49265989885.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=use+android+phone+as+a+microphonePDF 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_off0000e541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE541 18024 bytes
SHA-256: 3c92f49cbbf54ee8961156797ef9a011632b16a82193aa77504f79b61123081d
font_01_sfnt_off00011428.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11428 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C3F 10640 bytes
SHA-256: 87c6b40ddca5e4477f900ef5810c1d6d18d9062ab5973412e5a8f1aafe36f77e