Malicious PDF — malware analysis report

Static analysis result for SHA-256 7dc1aa7bf4381c61…

MALICIOUS

PDF

75.7 KB Created: 2021-09-17 15:32:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 1079d84783b75d02d7d630eeb3758221 SHA-1: ec1530d9a59d83bdfe71409bc84b7732cb9669ed SHA-256: 7dc1aa7bf4381c61cf5388b9607a6b1be639dd99629336f296d4c536522f0e55
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, directing users to download files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of external URIs and a link farm on disposable hosting suggests a tactic to obscure the true malicious destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://laborke.ru/uplcv?utm_term=ragnarok+x+next+generation+download+android PDF link annotation
    • http://kftchem.com/upload/files/25984570779.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/fometokivepebozoxut.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/75001790010.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/941612171.pdfIn PDF document text
    • https://foundationkuzmanov.com/files/85591133187.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/titubugula.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c9aa8e3b4---wumitumonino.pdfIn PDF document text
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/72206858416.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/rigosufososotekanefakob.pdfIn PDF document text
    • http://krishikhabar.net/assets/ckfinder/core/connector/php/uploads/files/15264892307.pdfIn PDF document text
    • http://braghieriarchitettura.com/userfiles/files/26784049918.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/biwumakulobaj.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/walerowu.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/16142deb723066---38310073266.pdfIn PDF document text
    • http://smelawservice.com/file_media/file_image/file/zexabinilugajuwifuwifak.pdfIn PDF document text
    • http://gaia-onlus.org/userfiles/file/zanorurinez.pdfIn PDF document text
    • http://dakov.hu/_user/file/76421494505.pdfIn PDF document text
    • http://formpart.com/upload/ckfinder/files/71536663744.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/58636783970.pdfIn PDF document text
    • https://braintreeclinics.com/app/webroot/img/files/taguginawil.pdfIn PDF document text
    • http://recit-de-vie.fr/userfiles/file/janorupafuwizuxewogolus.pdfIn PDF document text
    • https://123natura.com/stockages/files/dotaf.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///tesuga.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/ziwirurakulusunigamupova.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/94431561062.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_off0000c33f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC33F 10580 bytes
SHA-256: 421e7d54923768b6aa30b16355fdda22c5d06b46f64f71b94e0da8e67e7dcfb1
font_01_sfnt_off0000db61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF373 17624 bytes
SHA-256: 4c7ee8c1a01afbfd2d8d039155cc7dd3b2d3d0df31c29b45270020644adf0e8c