Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f13813713c6c78b…

MALICIOUS

PDF

97.1 KB Created: 2021-09-08 20:15:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1505bbc9f5a719038a1c08dff350cc95 SHA-1: e846d8b2eda56182e268f216de6bf62ab6652342 SHA-256: 8f13813713c6c78b179acc262a1ebe22e93d3fe069fc07a3a6bdbeb3a0d4549f
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, indicating an attempt to execute code upon opening. It also features numerous external URIs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 5

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://malopolskiszlakwinny.pl/upload/File/vukezinutawe.pdf In PDF document text
    • http://hkacca.com/userfiles/dajotowagajifosaladobupag.pdfIn PDF document text
    • https://booknowrentalimo.ch/userfiles/files/rojutesizijowewor.pdfIn PDF document text
    • http://thepnguyentran.vn/media/ftp/file/82329934162.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/47837087414.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/vuxabodafibabonizixibiva.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/xedijuwujuleduzexo.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/96951578300.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/giwimozoze.pdfIn PDF document text
    • https://worldmedglobal.com/userfiles/files/12035343064.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/sasolatufalikibijolu.pdfIn PDF document text
    • https://digireg.ch/upload/55991539740.pdfIn PDF document text
    • http://pyroglobal.sk/app/webroot/files/userfiles/files/54390190301.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613316f34b244---53160402697.pdfIn PDF document text
    • http://nagakuratrading.com/js/upload/files/rizivab.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/85143807913.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/26934038799.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/bupopowoxe.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/57235156595.pdfIn PDF document text
    • http://dsraxys.com/uploads/91326025696.pdfIn PDF document text
    • http://ocvitlucky.com/vietkiendo/upload/file/14167732890.pdfIn PDF document text
    • http://25630638.kad.tw/kads/ckfinder/userfiles/files/75293343476.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613414d056614---punefuwifilugifisated.pdfIn PDF document text
    • http://montpellier-businessplan.fr/mbp/upload/images/images/upload/ckfinder/ripumixa.pdfIn PDF document text
    • https://rossbeede.com/userfiles/file/93522388579.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/3677368139.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=simone+de+beauvoir+the+second+sex+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_off00011369.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11369 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012b80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B80 11320 bytes
SHA-256: 1facd51233082b8adaf698afc0923c6c724319c8499177c08b98d77c55bd954a
font_02_sfnt_off000145bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145BF 18876 bytes
SHA-256: bac504f02d43d77d64d51c5dec99a215e6d2f43b1f08cf0ddd3607104d34568b