Malicious PDF — malware analysis report

Static analysis result for SHA-256 920e366d7daaaa21…

MALICIOUS

PDF

89.3 KB Created: 2021-09-08 00:50:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4c772fe0d08e3c18e022027a7e74daf6 SHA-1: 608f7b5374db636d19bcb84e40570d7c9acf8703 SHA-256: 920e366d7daaaa21a501871a297f93ae675406d65fec7b9b7070ada064d67715
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to external resources, including a link farm hosted on compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's part of a campaign to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://zhbiotech.com/CKEdit/upload/files/55136936731.pdf In PDF document text
    • http://ttlh.vn/storage/ckfinder/files/13454192813.pdfIn PDF document text
    • http://rld-carbon.ru/file/juxesufegadogavorevava.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acef2ab51bf---duxusilikip.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/roferimevosakixud.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/xelikal.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/33021106859.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/3f2d942e32ab8eefeb25d7f2f1b259aa/ranarimevine.pdfIn PDF document text
    • https://mobilieroccasion.fr/uploads/file/8366305168.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/malipiko.pdfIn PDF document text
    • http://fashioneducation.ru/userfiles/file/27178321749.pdfIn PDF document text
    • http://r2doodles.com/clients/4/4a/4a4ed909dcef54c1e3ec6a0ce1d29f2d/File/7569506625.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/78570198017.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/ziviboleke.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/13891870659.pdfIn PDF document text
    • http://atlonnuri.org/UpLoadImage/editer/files/63925755069.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/leboresatefew.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/1401f8b068a84c8dba2d958cb8a8784e/37273190710.pdfIn PDF document text
    • http://faceconnects.com/ci/userfiles/files/zesazukikakatajovule.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/3f2c90c6cee3e0341e487d0d8aa8b063/26028422362.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/92663776206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=communication+meaning+types+and+characteristics+of+communication+pdfPDF 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_off0000f26c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26C 11268 bytes
SHA-256: 7ed79a52b959edd9b5ccdff53b6871e400e0fbb118a3e869ddf5618af80a32d3
font_01_sfnt_off00010c86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C86 18720 bytes
SHA-256: ca5f91fa119b63466eb536ad94f8bd9dbe51130c7ff596b0ab86ab0b2b0079a2
font_02_sfnt_off00013cef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1