Malicious PDF — malware analysis report

Static analysis result for SHA-256 be465efc4ad7bd17…

MALICIOUS

PDF

92.0 KB Created: 2021-09-15 19:35:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f6a9d7f687172effebee5402c4de0e4d SHA-1: 305649e23b54a7569980ca89bfbab146d5a05dae SHA-256: be465efc4ad7bd17a8e3898a0a62175673173e50ba73d15bd6e496459667a0a2
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF is part of a link farm designed to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://irlanc.ru/uplcv?utm_term=android+core+apps PDF link annotation
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613392979d1b2---noboje.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161397f3ebe182---lijuvo.pdfIn PDF document text
    • http://1night2daytour.com/ckupload/files/4441103315.pdfIn PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/90969573603.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/ap2kggbq71esi3e9obo01v4ban/22116551044.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/50338432444.pdfIn PDF document text
    • http://kruengrangthai.com/files/files/dojegobufedoximalejowa.pdfIn PDF document text
    • http://www.mattig-accounting.bg/fisiere/file/pewefovogivete.pdfIn PDF document text
    • http://wmsone.com/eimages/file/7800135727.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/rerirekuwopotopuxidijab.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133d6a7254a8---20341060617.pdfIn PDF document text
    • http://zamgph.com/FCKeditor/editor/filemanager/connectors/php/uploads/file/070450116334.pdfIn PDF document text
    • http://njchemland.com/upload/files/doxujusuzolaxeposiv.pdfIn PDF document text
    • http://dtmaso.com/public_html/Imagens/file/siwuton.pdfIn PDF document text
    • https://styliststudios.com/imagesTE/file/92474350897.pdfIn PDF document text
    • https://vinniescustoms.com/userfiles/files/26686460310.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612edb46007a0---22256145636.pdfIn PDF document text
    • http://htwy.com/upload/file/xikufives.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/6802989545.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed230267e9---90912483487.pdfIn PDF document text
    • http://czernavendeghaz.hu/admin1/file/gizafimebebewid.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/60440566783.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/nemopepazuxusibadawodi.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/putugudixow.pdfIn PDF document text
    • http://afro-safari.com/upload/files/55043546886.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_off000103af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103AF 10344 bytes
SHA-256: abb85888b1c6e0c3a53307d943b93ef41bbe38b78236982454a7aa10accef94c
font_01_sfnt_off00011b1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B1A 17808 bytes
SHA-256: 83f23cdaf8524bccac387f19b8f8b4dc481a782f890fe43383385be94b35532c
font_02_sfnt_off0001490b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1490B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1