Malicious PDF — malware analysis report

Static analysis result for SHA-256 d375660908b0f63c…

MALICIOUS

PDF

92.8 KB Created: 2021-10-18 23:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a7455bd5695f7d0c19cb1f7d5018db13 SHA-1: 591d91d54045eec231c13466fc38ae3d8a5a5ad5 SHA-256: d375660908b0f63ce26c7b5798ddacc05aab2d5aa2bc5e4af3d40dcdc46543b6
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://custom-mugs-factory.com/uploadfile/files/pumidol.pdf In PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/5320588188eaa60327c7cd9e49d539b6/26963107742.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/74749922657.pdfIn PDF document text
    • http://didopack.com/files/nebolunemizu.pdfIn PDF document text
    • http://cwpni.com/userData/ebizro_board/file/31249060536.pdfIn PDF document text
    • http://abwingsjanaf.com/uploads/files/jefenebemawuduja.pdfIn PDF document text
    • http://hospitalitan.com/sites/default/files/file/57727174486.pdfIn PDF document text
    • http://mega.kz/media/upload/files/puzavufanedekozizasidofe.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/19884878010.pdfIn PDF document text
    • https://pincodehub.in/userfiles/file/taniwitozokadekigaz.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/5913fe71a4aa750abc9ba553a6bce3c7/nevegumolejagosowasovitum.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/13304783875.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/vipowezepegutikijotaluge.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/dowafe.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/jagafoxepe.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614208c31a45e---kamepabomaf.pdfIn PDF document text
    • https://sua.vn/uploads/userfiles/file/63514664339.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/172122333009.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/95428364089.pdfIn PDF document text
    • https://meridianchem.com/meridian/ckfinder_userfiles/files/42079680621.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/widofariluj.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/85519120490.pdfIn PDF document text
    • http://travellerisland.com/files/padodezenemogur.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/20219262313505842.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/dijoritobu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/7xhmvLXWVJc/uplcv?utm_term=problemas+de+ecuaciones+de+segundo+grado+de+2+eso+resueltosPDF 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_off0000fcec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011503.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11503 11072 bytes
SHA-256: ac4fc1b71ea97923c664122b7db3b4abd968f1baed6a22cc8a0c1d546daf949a
font_02_sfnt_off00012ea0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EA0 20508 bytes
SHA-256: becb17766d0125b48aae28be76a6f81c6f897966cd9c7033efd9bfae6b7bd5c5