Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b5ca9c94f131b23…

MALICIOUS

PDF

88.2 KB Created: 2021-08-08 05:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 089061a12917c7a7383263ec2c531e87 SHA-1: d64394f606a98831fc5ac5211156ddcee4d9be4b SHA-256: 5b5ca9c94f131b23d41c0db8c348c77797e2da821352cf2229e512fa208973ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. Heuristics indicate it functions as a link farm, pointing to multiple compromised WordPress sites hosting other PDF files. These secondary PDFs are likely part of a phishing campaign or a malware distribution chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9c59d5de5---48834954701.pdf In PDF document text
    • https://www.nexidia.it/wp-content/plugins/super-forms/uploads/php/files/c77c0e28211f005c2509965b5cf06624/wupeduxelerixegogaxu.pdfIn PDF document text
    • http://cropscipublisher.com/files/upfiles/file/7247215992.pdfIn PDF document text
    • http://greddy.com/admin/common/ckfinder/userfiles/File/78682095003.pdfIn PDF document text
    • https://mimpishio1bet.com/contents//files/wokufenaronipapinen.pdfIn PDF document text
    • http://valsadindustries.com/userfiles/file/lupewuxewipakovali.pdfIn PDF document text
    • http://aptekainternetowa.net/_mdm_apteki/file/pixixef.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/13729879672.pdfIn PDF document text
    • https://aonetreks.com/uploads/file/fupozuroneralilanivo.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog//file/muwubetulimi.pdfIn PDF document text
    • http://biomehl.com/images/content/files/22905541250.pdfIn PDF document text
    • http://leton.pl/userfiles/file/61727977701.pdfIn PDF document text
    • http://sacoorhealth.pt/site/upload/file/visonatapotajaxorixok.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210602_201620.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1428a8327e---vunavojegajubudezab.pdfIn PDF document text
    • http://fitviewer.biz/files/file/wuwawaferarovijavazo.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/padekozufu.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/vh4r4m1pa21djukd13koauhev1/72310350594.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f93519e24---7549102887.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bdf8744ee18---bobopolowusavirim.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/0e3f92aa4fe5e22b1b88b999db7bf68c/42336003751.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=program+clicker+keypad+garage+door+openerPDF 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_off0000f205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF205 17596 bytes
SHA-256: ca739fa9fa881b187bdeaed54d21bbcb42d9e6a5aa23cf7362cdc966382ff3d4
font_01_sfnt_off0001205e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205E 10796 bytes
SHA-256: 27f4b082907f9c6d85985b6a6e99234e407d40af8f2cf27d08c23db00f2cdce3
font_02_sfnt_off000138fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1