Malicious PDF — malware analysis report

Static analysis result for SHA-256 a67801dbb5411f50…

MALICIOUS

PDF

73.8 KB Created: 2021-09-28 11:31:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b5e66dff2c98ceb21cf178b1611a6911 SHA-1: 0f0544813c20b9e37028ef2779023233e7954475 SHA-256: a67801dbb5411f5018a307d186578dbe4e055a78eb2c4bb67d4318a0b0fad288
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to numerous external PDF files, one of which is hosted on a domain flagged as potentially disposable. The presence of external URIs and the nature of the link farm suggest an attempt to manipulate search engine results or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://thingstodobahrain.net/ckfinder/userfiles/files/dixuzopabunetomunefajudat.pdf In PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/88351816932.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/sorilunelajudodeze.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615042b876556---23168666621.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/totokupurufigusutajidunor.pdfIn PDF document text
    • http://gangwonbnb.com/FileData/ckfinder/files/20210920_3FF044D3C5D44A01.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/39863337211.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/36686642674.pdfIn PDF document text
    • https://dobski.pl/userfiles/file/7464625526.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/38574962471.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/gepunaxuv.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///xezorizukilumipewar.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/wasunagulizopukufe.pdfIn PDF document text
    • https://beauty-full.ru/uploads/files/pakowuvutufujebuwopazitub.pdfIn PDF document text
    • https://aljuboori.com/userfiles/files/44058506598.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vikotikemejowemov.pdfIn PDF document text
    • http://bienbao.net/uploads/files/sawirodoxumosofa.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/14551622458.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161511ced54ce9---bizuxunupifu.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/3002240684.pdfIn PDF document text
    • http://prepearl.com/uploadsfile/vigazuxutewuvu.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/58056498517.pdfIn PDF document text
    • https://wasael.com/userfiles/file/ribijojowevubo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=super+marios+bros+3+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_off0000bbbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBBE 17844 bytes
SHA-256: d0fd13b078d456e8873a670b79dfe272332d35d42af6e1bad16a9ac10fd411ea
font_01_sfnt_off0000e94f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE94F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10166 10744 bytes
SHA-256: aba7d724db99e744ba05d9d965f0709ae66d6531fc0a4b692cfd58439f76c3a5