Malicious PDF — malware analysis report

Static analysis result for SHA-256 c61d249cdb5f36ae…

MALICIOUS

PDF

69.8 KB Created: 2021-09-29 09:44:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b31aad8e9b3de8c51ebbfbe23a01f67b SHA-1: 9775f7773915f595b303059f1fda3c509e26693f SHA-256: c61d249cdb5f36ae9aa82c2390e0d0bf90e611e20fe2b79ee155bc67d66d749c
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, many pointing to suspicious domains, and is identified as a link farm. While no scripts were explicitly extracted, the PDF structure and the presence of many external links suggest it's designed to redirect users to potentially harmful content or facilitate further infection vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://nichecnk.leaddeehub.com/userfiles/files/wovexo.pdf In PDF document text
    • https://amt-alarmy.pl/userfiles/file/dawopogurokoxomidoxuno.pdfIn PDF document text
    • https://truonggiangcompany.com/userfiles/file/xokakubunetatosowavej.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210908_79810ECA42BA2713.pdfIn PDF document text
    • http://changjiujz.com/uploads/files/202109060307547042.pdfIn PDF document text
    • http://jezirka-biobazeny.cz/UserFiles/File/51361528262.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/bozotudadimusasajelitixub.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/wubakof.pdfIn PDF document text
    • http://keyseries.us/userfiles/file/teparopuroserixowobofiz.pdfIn PDF document text
    • http://arablift.net/userfiles/file/36829801924.pdfIn PDF document text
    • http://parkety-patemal.sk/files/file/nejaxamosorojijaxabek.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/5cdad112b300cb7054094b83e411b08c/befalarovujase.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/kudexulegadi.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/37626167653.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/26303096520.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/89567236902.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/poreruninaxagagifodax.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/nitusofojojas.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/nobezufi.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16150d5e9e967f---budoxanejulisizo.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/getikadoletaman.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/muginusibuzaga.pdfIn PDF document text
    • http://origo.ws/userfiles/file/jovefowavavajafepa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=top+100+offline+gamesPDF 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_off0000b21e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB21E 10640 bytes
SHA-256: 22c540383b1ab2e49baa0988540385ee8c2953a0e2272f453159946a1c67699a
font_01_sfnt_off0000ca75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE287 15420 bytes
SHA-256: 2c945820254179f65d5f506af2e385a5dbd99fa24f00666840da3ec6f3583717