Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf129ae3e6a1afb6…

MALICIOUS

PDF

83.1 KB Created: 2021-09-09 17:45:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f6a890e681d17f46c42e03341320162f SHA-1: 66814abb2a810c98e653a18faa1eedd12e1179c1 SHA-256: bf129ae3e6a1afb6a1471a0d0aae7c032352ba8426d8e2ecc72b640e056f0d69
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest this document is designed to redirect users to potentially harmful websites. The document body was unreadable, but the overall structure and URL patterns point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://chcial.ru/uplcv?utm_term=litmatch+mod+diamond PDF link annotation
    • https://luckyfood.itweald.com/uploads/files/6135f439bb9a4.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/bapivopimirajanebi.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/74334178207.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/xikokemixuvun.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/16130440c8d617---sokokefikejorizelapuko.pdfIn PDF document text
    • http://honyi.tw/ckfinder/userfiles/file/68856983262.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210902115746.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/fonavisum.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/10561756343.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/rasupudibipemugunafoviw.pdfIn PDF document text
    • http://centronegozi.com/public/65244071781.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/1642278147.pdfIn PDF document text
    • http://dtyxbpzx.com/filespath/files/20210908062912.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/bawek.pdfIn PDF document text
    • http://interroadholland.nl/userfiles/file/kumeze.pdfIn PDF document text
    • https://2acontractor.it/images/file/juburafa.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/53330832452.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/10551228055.pdfIn PDF document text
    • http://hamzalegalservices.com/userfiles/file/2951115414.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/95637246367.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210902160015.pdfIn PDF document text
    • https://efnnma.org/files/file/2263298694.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/zobiseviw.pdfIn PDF document text
    • https://www.champagne-auge-dascier.com/ckfinder/userfiles/files/59449009161.pdfIn PDF document text
    • http://keramann.ru/uploads/files/mekazoverunaniwekof.pdfIn PDF document text
    • http://cpviettin.com/upload/files/romisutope.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_off0000e02b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE02B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f83d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83D 18484 bytes
SHA-256: 56ac53bab9d94bb022fea38486c5c59074bfb6915b01b2078b3bf00fa3c9fc71
font_02_sfnt_off00012836.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12836 10148 bytes
SHA-256: a3e7d7d4ced6b4737f05a48bbf3bf22255133e25e98ed5bfc17aefa0aef99010