Malicious PDF — malware analysis report

Static analysis result for SHA-256 556d2a48bafea52e…

MALICIOUS

PDF

69.4 KB Created: 2021-09-20 20:17:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 46c0372b251e7c602f6725b8b6177bb9 SHA-1: 28b13e429a320c6218e40aacefafb246af26ed96 SHA-256: 556d2a48bafea52e95a310a708abfc38fbf1c3293ca301aea6ab4c2f5eaaf942
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and employing UTM parameters, strongly suggests a phishing or link-farming operation designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute malware or conduct phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=find+quadratic+function+given+vertex+and+point PDF link annotation
    • http://kinel-hunter.ru/upfiles/file/17141099244.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/bapuvotajume.pdfIn PDF document text
    • https://mpressivelabels.com.au/application/third_party/ckfinder/userfiles/files/wunadipebovep.pdfIn PDF document text
    • https://clickbox.ro/images/file/tazesosijadobofugigipuw.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/95816147914.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/44017124921.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/86570203758.pdfIn PDF document text
    • https://anesaportugal.org/upload/file/54340741424.pdfIn PDF document text
    • http://debseven.net/UserFiles/File/57835535825.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/10266012720.pdfIn PDF document text
    • http://ville-dammarie.com/ckfinder/userfiles/files/zorofefodezufuxuwenebiro.pdfIn PDF document text
    • http://agavietnam.com/img/files/gijenipolubunajipezuputuv.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3a2590d79---denutu.pdfIn PDF document text
    • http://siciny.eu/userfiles/file/mozokez.pdfIn PDF document text
    • https://andana.us/files/files/53564004083.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/23480827887.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/a9ljaoh6rdjco7i23fq9mma39u/marakavasub.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/16610509557.pdfIn PDF document text
    • http://rowerowaszkola.pl/imgturysta/files/zakimutovavu.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/fedonajuradopelemidubofo.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/wofuwiruduzizibimike.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/jasatasokakera.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210917034906.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/wumugowim.pdfIn PDF document text
    • 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_off0000b107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB107 14980 bytes
SHA-256: bb3b37cb1f8ebd2f6affa811f0829f6b7447a92c6d75dfd62f3560546021c4fa
font_01_sfnt_off0000d6fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6FB 10972 bytes
SHA-256: 12e338b320b1573f92bddcb98025259dc1b240fa72d014eab039792eefd238f3
font_02_sfnt_off0000f018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF018 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1