Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8524db585831ce7…

MALICIOUS

PDF

83.6 KB Created: 2021-09-19 11:36:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4753c183e38d76b4b98d3676365c2cc1 SHA-1: 6197ebc483fb3a681375f9046c1757a0fb8569f8 SHA-256: c8524db585831ce7d2e9ce02abb66fe32634197118cccdf2e006da3d9a52853a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the presence of multiple unknown URLs points towards a potential download or redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/3aeced06f73bd9e8f67a6da3878e2b3d/26871524790.pdf In PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/dejasivar.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/lemovas.pdfIn PDF document text
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/2962866797.pdfIn PDF document text
    • http://ibtaker.ps/userfiles/file/81658298013.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/zazot.pdfIn PDF document text
    • https://gencshow.com/upload/ckfinder/files/41250882189.pdfIn PDF document text
    • http://wingtsunkungfu.ro/imagini_ws/mujinanetivelutenupage.pdfIn PDF document text
    • http://195exim.com/datas/files/36575463474.pdfIn PDF document text
    • http://esipro.be/userfiles/file/79141668702.pdfIn PDF document text
    • http://hanilkwanla.com/uploads/files/lusizidumiwikoxoguzufud.pdfIn PDF document text
    • https://tannhatviet.vn/upload/files/96028783542.pdfIn PDF document text
    • https://network-italia.it/file/25529142214.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/97813824380.pdfIn PDF document text
    • http://puginternational.com/ckfinder/userfiles/files/tabilasakon.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210917105431.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202109152333456696.pdfIn PDF document text
    • http://eubeer.vn/uploads/files/tisasupixononotu.pdfIn PDF document text
    • http://antoniolescio.net/userfiles/files/57556177942.pdfIn PDF document text
    • http://tatishev.ru/admin/ckfinder/userfiles/files/24466770949.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/44d3f846ca95bf595152f342643b9290/jaguzogajarizonimufudo.pdfIn PDF document text
    • http://prplus4u.com/ckupload/files/99026187731.pdfIn PDF document text
    • http://linker-apps.com/files/pabusovonuvilirup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=layers+of+the+rainforest+printable+pdfPDF link annotation
    • http://elezioni2014.gds.it/userfiles/file/gegonuxibo.pdfIn PDF document text
    • 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_off0000e0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0CE 18136 bytes
SHA-256: ce0be8bc66895e5417a06b836be5cf9dde30e9888fbf8354515b17a78fc69fe5
font_01_sfnt_off00010fc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC5 10808 bytes
SHA-256: ce83060d6597f3f200ba99213ddcb7c3b24059b9e6e6fd43b12bed0d1149fec1
font_02_sfnt_off0001285c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1285C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1