Malicious PDF — malware analysis report

Static analysis result for SHA-256 50dc6d0f5a04edb3…

MALICIOUS

PDF

78.9 KB Created: 2021-10-09 04:52:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 995f9eae9095a5c2db0b36d9858e11aa SHA-1: 34421baf250f57aaabfa9ce4497bc4ae89c21532 SHA-256: 50dc6d0f5a04edb31e22acdb9e75645487327151cf30ace1545f7fbc8e50ce8e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The presence of numerous embedded URLs, many pointing to disposable domains or link farms, strongly suggests a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://pbpharm.com/upload/files/64695798497.pdf In PDF document text
    • http://ulleungroadtour.com/FileData/ckfinder/files/20210908_2D0BF505425AEEEF.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/tutevoz.pdfIn PDF document text
    • http://brno-skoleniridicu.cz/ckfinder/userfiles/files/22163455894.pdfIn PDF document text
    • http://liga-stf.ru/i/upload/files/89289023339.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/fee82d74397c27d616865b863507d3af/64483830244.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/42944175811.pdfIn PDF document text
    • http://zamgph.com/FCKeditor/editor/filemanager/connectors/php/uploads/file/180322507967.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/27215520436.pdfIn PDF document text
    • http://fuyu.010bi.com/ckfinder/userfiles/files/10320837595.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615368e20ab96---xaxogef.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/03/kosukobobiw.pdfIn PDF document text
    • https://leonardscopysystems.com/home/leonards/public_html/ckfinder/userfiles/files/zesenodirivojo.pdfIn PDF document text
    • http://dd-eng.com/files/files/49930171250.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/85632747609.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/jexamipen.pdfIn PDF document text
    • http://modelseafarm.com/kweb/ckfinder/userfiles/files/boluxoligazaberijejifib.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/wedazojorasinumeruzojow.pdfIn PDF document text
    • http://impactpluslearning.com/ckfinder/userfiles/files/dibakagamodogipa.pdfIn PDF document text
    • http://iphastkala.com/userfiles/file/zuvefidevikeronukanixep.pdfIn PDF document text
    • https://delcinfo.ru/img/files/files/38424114493.pdfIn PDF document text
    • https://mfdesign.hu/files/file/14211811433.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/rilikikole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=most+annoying+clichesPDF 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_off0000cf3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF3D 18348 bytes
SHA-256: 2b797c7f1f77c464046528c21293bb751657d22c74826e7d005c7fee848660cd
font_01_sfnt_off0000fe51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011668.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11668 10516 bytes
SHA-256: a1bd7c10b5e6339a5269255b746070545018ead8f8627e269ae1d73b3cbe36a6