Malicious PDF — malware analysis report

Static analysis result for SHA-256 8236bfb6e00d360d…

MALICIOUS

PDF

71.5 KB Created: 2021-10-03 13:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: d17b6d9dfaa8216815959ee41506bc9f SHA-1: 3553d4cf69a039bf9e307dd4da73f22cbfaf076d SHA-256: 8236bfb6e00d360d061a1e162b3915770caf8fc88f9c310de80e50f90a0d819b
66 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a malicious intent to redirect users through multiple sites. The ML classifier also flagged this PDF as malicious with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://comobrew.com/newsite/images/user_uploads/file/49832406406.pdf In PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/palulodifexaramam.pdfIn PDF document text
    • https://www.wroclawmodelshow.pl/ckfinder/userfiles/files/19347547274.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0fe03466e---zuluvuwenuxiz.pdfIn PDF document text
    • http://gardatrans.com/content/Files/kevisumigetum.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/kulujuxolupimiwifov.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/sukefutixepidisujesewudu.pdfIn PDF document text
    • https://dodatnagarancija.com/userfiles/file/vavetikasazodu.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b122f73cce---morovedesemu.pdfIn PDF document text
    • https://majubesar.net/contents/files/lomuvufododigorizaz.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/5024529880.pdfIn PDF document text
    • http://botaierpharm.com/upload/files/pemafamalemimuk.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/38966866749.pdfIn PDF document text
    • http://kaymccarthy.com/immagini/file/wawalujikevivadifolawaw.pdfIn PDF document text
    • https://art-eria.pl/mandarynka/pliki/files/37426098090.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/51186988401.pdfIn PDF document text
    • https://thietkeweblongan.com/upload/files/tadoluzalefutesime.pdfIn PDF document text
    • https://reviewz.eu/app/webroot/files/userfiles/files/45269298314.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/52459770921.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/mefosanenibamikanug.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/34884162776.pdfIn PDF document text
    • https://meesens.be/KrMee/Tekstverwerker/42149420112.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=education+production+functionPDF 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_off0000b2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DD 10352 bytes
SHA-256: 66ed026c4d4499064ffda3dd7c1d936d4f391441e772a06259bf81e90b6d228f
font_01_sfnt_off0000ca4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE260 17892 bytes
SHA-256: a5135dab65c981a3efc1d656d393bf3bbceb1141f8ddff5d141ac3eb4d46cc66