Malicious PDF — malware analysis report

Static analysis result for SHA-256 b50fb5082387b09f…

MALICIOUS

PDF

71.7 KB Created: 2021-09-08 09:02:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: bf02f15d2eadd4ffdc4e932fcb01ffac SHA-1: fdcab43c4174d4e5a334b0599dde6d7ac5847523 SHA-256: b50fb5082387b09f677e505e85c1f6079f3edcf6c548d15371a871f22fbb2389
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=submarine+hydrodynamics+pdf PDF link annotation
    • http://nawooelcs.com/upload/userfiles/2021/06/files/210614174831.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/85685104271.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/tefijizexamom.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/4f432fc12846003d7c15c58295d4f8c1/lotumolememagape.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16078788dcea57---44632494002.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42579537928.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/xatulisolepug.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/kfdh62ugbvsf7k3sgu2bbcio06/tasepajaro.pdfIn PDF document text
    • http://bakerfamreunion.com/clients/1/13/13be4b03bdabdd3a133c3ee64ed6201b/File/52782540721.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/tijujikelusip.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/85515453732.pdfIn PDF document text
    • http://bagiez.de/userfiles/file/6008588506.pdfIn PDF document text
    • http://fullx.net/files/meduvusudasimi.pdfIn PDF document text
    • https://lotteppta.com/beta/assets/file/xupebikiloku.pdfIn PDF document text
    • https://bnovum.hu/downloads/8195702395.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/30362846063.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/33694236164.pdfIn PDF document text
    • http://dongtienlamnghiep.com/upload/file/89251956353.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/27737574798.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/s9ou1ch7hggjuii0pdudm2d1m0/93317757860.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/zabimonakimagakuzedemoja.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/fuduputabunidifomux.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a825133175d---90650267503.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_off0000b83f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB83F 11168 bytes
SHA-256: 8578cc4f80dba84b73aa7a4de5808d853c83c7fc9af187a7e51dd4e1af6e5036
font_01_sfnt_off0000d1e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1E6 15304 bytes
SHA-256: 3ed48b0999dd3e6728f13a9b469ec54d010da5b5203cb94691a1513ab5e8cc65
font_02_sfnt_off0000f950.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF950 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1