Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3b5037fc0d87833…

MALICIOUS

PDF

76.9 KB Created: 2021-09-16 10:13:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 8a32f5414c4040ab7df72bd6d6503495 SHA-1: a68d3059ee3d569812ffae4b7d52ae8ad0d20ae4 SHA-256: b3b5037fc0d878330f7d3e872c79bdc522f34412065b5f8de5baed1b7b146429
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains embedded JavaScript and is flagged by multiple heuristics, including a critical ClamAV detection and a high ML score, indicating malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document's purpose is to trick the user into installing malicious software by posing as a necessary update or extension. The presence of embedded JavaScript further supports the execution of malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://mdcegy.com/app/webroot/img/fck/file/zoluzagefiburobujopuxefer.pdf In PDF document text
    • https://tfsroanoke.com/home/tfs/public_html/new/ckfinder/userfiles/files/95476290225.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/xexumipe.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/87523565885.pdfIn PDF document text
    • https://michelbarbot.com/upload/files/vavira.pdfIn PDF document text
    • http://icareonline.net.au/ckfinder/icare/files/misaxize.pdfIn PDF document text
    • https://gegeny.hu/uploads/file/pelavoset.pdfIn PDF document text
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/kikipipuf.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/vukomilesepi.pdfIn PDF document text
    • http://insei.eu/userfiles/files/13287946974.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/pubajivapevezut.pdfIn PDF document text
    • http://k-ookuma.com/js/upload/files/37084163844.pdfIn PDF document text
    • http://budaors.varosom.hu/userfiles/files/59292691087.pdfIn PDF document text
    • https://contemporaryteas.in/admin/uploads/file/6630804826.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/93094549104.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/45631074495.pdfIn PDF document text
    • https://kiptep.ru/file/76492259608.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/73657489081.pdfIn PDF document text
    • https://spacio.hk/attachment/file/zekuwepujuvegaxowedat.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161372029bb7f2---gazetosodip.pdfIn PDF document text
    • http://ubytovani-budejovice.cz/picture/vtextu/file/38614305780.pdfIn PDF document text
    • https://edarky.net/data/file/83561467776.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/50654264313.pdfIn PDF document text
    • https://businesslife.com/content/file/wavawobitumasokipipidevi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=in+clash+of+clans+how+to+get+free+gemsPDF 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_off0000c91f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC91F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e136.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE136 10728 bytes
SHA-256: 06d71759444557341559a334f474301e40c31dc9a8c9eb1a0a6e71c899dffdae
font_02_sfnt_off0000f9cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CC 17052 bytes
SHA-256: 44cebb6998249ddb49bb3368020b69d2919d829bfa069bb1effb4d119e43c9e8