Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c15df5a8d2717f…

MALICIOUS

PDF

88.8 KB Created: 2021-09-12 15:37:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 80842d7b52aab8ea51a441acc888a7d0 SHA-1: 8c5514a4c441522f5f0de19870487b2bf32afda9 SHA-256: 88c15df5a8d2717ff9a85e3a041d9f9e08b3c679263b819a73e10efe1a5da20b
166 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and a machine learning classifier, indicating a high likelihood of malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests a social-engineering attack aimed at tricking the user into installing malicious software or providing credentials. The numerous embedded URLs, many pointing to PDF files on various domains, are consistent with a phishing or malware distribution scheme.

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
  • 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.
  • 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://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/25af8b9d285a16b1648e4b937247c4f0/petefulaw.pdf In PDF document text
    • http://skncn.com/u/files/rijopaxuk.pdfIn PDF document text
    • http://linza-market.ru/upload/files/fugige.pdfIn PDF document text
    • http://duoctruongxuan.vn/userfiles/image/file/fijoramuwex.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/pipaniwubakutomus.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/tiropixilufove.pdfIn PDF document text
    • https://medius.sk/userfiles/file/karomugodejizebu.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/vaxab.pdfIn PDF document text
    • http://vividconcept.in/userfiles/file/30578494228.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/85324438534.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210912_4C7D4012DDAC28CD.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/vetatosajabupitukuzikej.pdfIn PDF document text
    • http://mebizstekla.ru/userfiles/file/57114337386.pdfIn PDF document text
    • https://getadoc.in/ckfinder/userfiles/files/buletelipufuzumagukeg.pdfIn PDF document text
    • http://linpus.com/app/webroot/userfiles/files/givobobakoda.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109090500281154.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/80889432589.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/50250731374.pdfIn PDF document text
    • https://infosantiere.ro/userfiles/file/97096073074.pdfIn PDF document text
    • https://jeevadhara.org/work/london/userfiles/file/sejafivufefirigebakuzini.pdfIn PDF document text
    • http://besteva.com/upload/files/30920740516.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/15833411845.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b45bd74f7e---jajibedidadurajo.pdfIn PDF document text
    • http://mediacast.vn/ckeditor/upload/files/wowawijuzolagubokomupogij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=subway+surfers+unblocked+76PDF 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_off0000f3fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C14 11104 bytes
SHA-256: 4858daa06224876af416abd2a94f5088d6130a769aa5e1fb564032d5447f8cb9
font_02_sfnt_off0001263a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1263A 18276 bytes
SHA-256: 8d9696f26045589c6e97ccd76d3a657311c2ef961aef189936a4b9003da88eba