Malicious PDF — malware analysis report

Static analysis result for SHA-256 873476f913335d1c…

MALICIOUS

PDF

70.2 KB Created: 2021-09-26 13:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 03eed6aec11fe25441576dce8c985a4e SHA-1: 98e04bb22ced60ea0470d0e1d36f775d92203f5e SHA-256: 873476f913335d1cefa86828296a21cfffe4970966bc22877975235e46b7e032
66 Risk Score

Malware Insights

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

The PDF document contains a high number of external links, many pointing to disposable domains, which is characteristic of a link farm designed to obscure the true destination. The ML classifier strongly flagged this PDF as malicious, and the presence of numerous URLs suggests an attempt to redirect users to malicious content or phishing sites. No scripts were extracted, and the document body was unreadable, so the primary indicators are the heuristics and the URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 4

  • 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 http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/ndaf4j03c8as6frigo4ok7pcd7/2000126995.pdf In PDF document text
    • http://abc-tel.ru/data/File/gezeguregoteb.pdfIn PDF document text
    • http://arhive.np-sp.ru/img/file/wozaxerabomuvorufuxivama.pdfIn PDF document text
    • http://lokalizacja-gps.pl/userfiles/file/geneliv.pdfIn PDF document text
    • http://modellszerviz.hu/userfiles/file/6177060570.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/37474801059.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/46233051805.pdfIn PDF document text
    • http://asbazainville.org/userfiles/file/tetodosuxexuvojuwe.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210923_715E6105D8EA61F2.pdfIn PDF document text
    • https://youkuvpn.com/upload/files/67907727599.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/madelaf.pdfIn PDF document text
    • https://swiz.eu/files/editor/mumerutikol.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/2762803098.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/6333114174.pdfIn PDF document text
    • https://triatlonshop.cz/userfiles/file/74624362097.pdfIn PDF document text
    • https://dental-essence.com/admin/userfiles/file/katuteroradodubosumoxolar.pdfIn PDF document text
    • http://cauthinh.com/luutru/files/68942450805.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/neruraxelafigesuf.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/e81e1c31a379a5b30c0a6964bbaa7dc2/38285103524.pdfIn PDF document text
    • http://www.hgekc.com/media/userfiles/file/58859385137.pdfIn PDF document text
    • http://rsport.eu/yonexshop/static/file/kozuribamufena.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/5020261631.pdfIn PDF document text
    • http://rpsbchamber.org/editorData/file/zuruwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=metal+slug+apk+3PDF 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_off0000af34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF34 10368 bytes
SHA-256: 453f61249d6c12105afd4cdb930db371bd71b038929278615316d101a308e315
font_01_sfnt_off0000c6e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6E0 17940 bytes
SHA-256: 1caddd1a4d6225e04db9bc686dedccbfcc8b1e34fcdbdf70d1cddf1fb05b4783
font_02_sfnt_off0000f3b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1