Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7b2e58751258ee…

MALICIOUS

PDF

72.4 KB Created: 2021-09-30 13:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: c3f30e3bde649e84c30c943750ae6e7c SHA-1: 86b93811249f21d40c44d10b9433f82144feb68a SHA-256: bc7b2e58751258eeba83d8a1329bbe6cc46606af92e9dfcc8ec9403ce6c8ca2e
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and multiple external URIs, with one specifically flagged as a link farm on disposable hosting. The presence of JavaScript suggests the document is designed to execute code, likely to download and redirect the user to a malicious site, as indicated by the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/futefewuvuzupex.pdf In PDF document text
    • http://sreema.org/FCKeditor/file/salixaguwi.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/47214628707.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/23413089833.pdfIn PDF document text
    • http://decentlogistics.pk/survey/userfiles/files/dinavonunazunid.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/motafawikilokif.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/57518284004.pdfIn PDF document text
    • http://dynamic1984.com/user_file/file/wuvijedetefupidogom.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/lipegorozotow.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/0cf26198381ab1d394e78b4aa5d139c0/11874687292.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/vavewejotuvaxafaxido.pdfIn PDF document text
    • http://neuroxl.com/images/file/6196966500.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/mosunumanexizi.pdfIn PDF document text
    • https://thietbigas.net/media/files/97892398558.pdfIn PDF document text
    • https://unaizahic.com/Files/files/nipanoga.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/9341569596.pdfIn PDF document text
    • http://zenpersonnel.com/UserFiles/file/kewaxuditeleremabajudekof.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/64543872770.pdfIn PDF document text
    • https://inprovitperu.com/ckfinder/userfiles/files/71227738855.pdfIn PDF document text
    • https://nffcd.org/userfiles/files/5987510848.pdfIn PDF document text
    • http://lagrupacio.cat/file/9325487112.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210922_73CCD59AC70E8B61.pdfIn PDF document text
    • http://wannawwannie.pl/userfiles/file/46931278052.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/xubunot.pdfIn PDF document text
    • http://huonglonghotel.com/uploads/image/files/77306073738.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=bachelor+season+25+episode+10+watch+onlinePDF 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_off0000b4bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4BD 17276 bytes
SHA-256: 2095b411ff7a0bae367d10806b6882cf0fa8d8daa8cc385d7ae56660665b9244
font_01_sfnt_off0000e109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE109 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF920 11176 bytes
SHA-256: 06e49cdb0a4343669e3356b41a424fd0e018c87ec9793f4b0088c8f9719b7bcd