Malicious PDF — malware analysis report

Static analysis result for SHA-256 73ea1a4c8c6eadb2…

MALICIOUS

PDF

69.5 KB Created: 2021-10-02 12:58:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1aaa3711b665fd80118f7c2e94edb1d8 SHA-1: 6297ab707476eeb5d585d7191c6ffaba4043bdde SHA-256: 73ea1a4c8c6eadb298283a09172081ebee9c0e28ebbedaa8f4d49862b6cc63d5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document that contains numerous external links, many of which point to other PDF files hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of external URIs and the link farm heuristic suggest the document is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ketchas.ru/uplcv?utm_term=deferral+of+corporation+tax PDF link annotation
    • http://speaklifeiamgreatness.com/files/files/jataniwa.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8aa9d708d---xurisedalapawazero.pdfIn PDF document text
    • https://a-1commercialkitchenservices.com/ckfinder/userfiles/files/16971510735.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/67113014698.pdfIn PDF document text
    • http://tallygroupkwt.com/uploads/file/jafijapeximebiri.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/mujuzidudatibikozatef.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/7838634304.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/majufadupuva.pdfIn PDF document text
    • https://sowlindia.com/userfiles/file/tevadugemulivo.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/lenigewesawoguxevat.pdfIn PDF document text
    • https://marsanz.pl/uploads/fck/file/kinejilozanulafunerugetuv.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/20211012054227633.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161459a0e071e1---30872735066.pdfIn PDF document text
    • http://swiftnb.com/ckfinder/userfiles/files/sewazinaxenivipasumafu.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/42368498371.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/vixejidaguropabo.pdfIn PDF document text
    • http://maxbrio.kr/files/files/74714029872.pdfIn PDF document text
    • http://unixsensor.com/uploads/files/202109121454029811.pdfIn PDF document text
    • https://otoform.com/upload/ckfinder/files/69664233379.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/88912972822.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210909_4ECCA566178954B2.pdfIn PDF document text
    • https://cargoservice.pl/cargoservice/userfiles/file/17026939027.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/84025581455.pdfIn PDF document text
    • https://unosms.us/userfiles/file/81804388701.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_off0000b229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB229 10408 bytes
SHA-256: 75f942d848f596b0439b978a05415fb9a83bc042023c5d91ee708a5373da3460
font_01_sfnt_off0000c9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D4 15136 bytes
SHA-256: cb0472cc860cd7cf9343fdac5155f58e0c08e630f05a64e10fc8ca625732ac9d
font_02_sfnt_off0000f029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF029 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1