Malicious PDF — malware analysis report

Static analysis result for SHA-256 73f928d3ca69c9a5…

MALICIOUS

PDF

69.5 KB Created: 2021-09-18 03:22:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 015c647870905fa6c61b55a80ccd8b75 SHA-1: 1453378089c7e27ab14b27d2c9e49f5d76c7d71a SHA-256: 73f928d3ca69c9a5c71a872c29db2d1697a891e5ae145e41ae489542ac1244ff
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and appear to be part of a link farm designed to redirect users. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or distribute multiple malicious links. No scripts were extracted, but the overall structure suggests a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://angelascanu.it/uploads/file/83039018298.pdf In PDF document text
    • http://gainliving.com/upload/editor/file/gotupotubijateje.pdfIn PDF document text
    • https://negaratoto.com/contents/files/luvinuj.pdfIn PDF document text
    • http://addisonplaza.abwingsmd.com/uploads/files/87089365978.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/4885635033.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/kubipa.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/73157654442.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/14541003837.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/93669919080.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/35079031666.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/22247722495.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/99463764367.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109171403305653.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/kepatomalupalofe.pdfIn PDF document text
    • http://tuanlongland.com/upload/files/losanudafilu.pdfIn PDF document text
    • http://dvg.asia/ckfinder/uploadfiles/files/zukadexi.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/75757998227.pdfIn PDF document text
    • https://dp-engineers.com/admin/userfiles/file/12834744021.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/zowuvetidozujozekaso.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/wobujuxigolezezego.pdfIn PDF document text
    • http://m2m2design.com/userfiles/26496158713.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb7f348a36---gikegonixaxubedalijoveki.pdfIn PDF document text
    • http://ansonseatery.com/uploads/files/81507151594.pdfIn PDF document text
    • http://elektrostroy.kz/ckfinder/userfiles/files/5267386600.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=io+games+first+person+shooterPDF 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_off0000b291.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB291 10712 bytes
SHA-256: 516aa2c899464c7c0ba4e05df5c8631ce0eaeb7f5f2ecb147bca5615f4ebb489
font_01_sfnt_off0000cafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE30C 14808 bytes
SHA-256: 9ce80c8c040a207fe5d7970cdd0a41892098bc3edf27b5c341b8becb12337427