Malicious PDF — malware analysis report

Static analysis result for SHA-256 c616bed99c141550…

MALICIOUS

PDF

83.8 KB Created: 2021-09-14 11:35:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 664c090f954456e40d4f94e2e72b6924 SHA-1: 71f6a5d0b4b66c92b0d8729f8c8ef768fe4ecc95 SHA-256: c616bed99c141550602892e937fbc00b3564d8f9ab9066ca7388fbb319c46a12
164 Risk Score

Malware Insights

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

The PDF contains multiple links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to obscure the final destination. The presence of a 'download button' heuristic and ClamAV detection as 'Pdf.Phishing.Trojan' strongly suggests a phishing or malware distribution attempt. The ML classifier also flagged this PDF with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gkia.org/kingkong/userfiles/files/fakegibovuwapuzubon.pdf In PDF document text
    • http://sooam.com/files/fckeditor/file/1253693628612fe9e3a8163.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/10356370672.pdfIn PDF document text
    • https://themis-lex.com/userfiles/files/wiwomexegafavogazewe.pdfIn PDF document text
    • https://bomberosdenavarra.com/userfiles_nexo/files/43985055900.pdfIn PDF document text
    • https://francoisdaulte.com/ckfinder/userfiles/files/28960037591.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/vukomilesepi.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/4479333806.pdfIn PDF document text
    • https://nileagriculturalindustries.com/file/91473524093.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/30588790828.pdfIn PDF document text
    • http://laptopplus.be/app/webroot/files/userfiles/files/jinolazofep.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/zuwobegu.pdfIn PDF document text
    • https://ckfinder.pamlskovnik.cz/ckfinder/userfiles/files/pibewe.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613e630e89a37---98836368895.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebc4a743b2---82353977360.pdfIn PDF document text
    • https://editionsitaliques.com/userfiles/file/35154480170.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/40633130758.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/povor.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/2e69e2e9b6a2aaf94dc00f6e37cf873b/zisuferizegoloko.pdfIn PDF document text
    • https://tonerihned.cz/userfiles/file/tebomokub.pdfIn PDF document text
    • https://dobre-akce.cz/media/files/file/volukujan.pdfIn PDF document text
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/fivedujawevinum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=farming+simulator+19+android+download+apkPDF 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_off0000e194.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE194 17884 bytes
SHA-256: 3d28c94cb0a93b5c7bb85ee923ea20972450dae1752ddec922f7f03dd9579c78
font_01_sfnt_off00010fca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127E1 11080 bytes
SHA-256: ff8957b4c54299cafa4bacf06cfbf676671cae9e82ae5da8b9f80c07ac805b4b