Malicious PDF — malware analysis report

Static analysis result for SHA-256 c556b70c24decd42…

MALICIOUS

PDF

72.6 KB Created: 2021-09-09 03:15:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8ced191f161d8d6f59686c698f6bd40d SHA-1: ab5d3b0bc7a26d77da69ff02408372b36abb2de2 SHA-256: c556b70c24decd42f28d6b523e4485ce7c7ce19f236b9ddc48f3ea4bb5ad0bb3
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which are hosted on disposable domains and utilize UTM parameters, suggesting a link farm designed to trick users into downloading files. The ML classifier also strongly indicated maliciousness. While no scripts were directly extracted, the structure and heuristic firings point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://krisoc.ru/uplcv?utm_term=old+road+rash+game+free+download+for+android PDF link annotation
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/99562401348.pdfIn PDF document text
    • http://mis.nrru.ac.th/gradjournal/ckfinder/userfiles/files/28432238296.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/gexebum.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/dewevolasevewuzaja.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/lizoxilopirazadu.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613858d37d947---bederalupetezobodovanasa.pdfIn PDF document text
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/tapatorivajiniva.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/mukububabelusok.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/36095638665.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/26100418735.pdfIn PDF document text
    • https://spotiverify.com/ci/userfiles/files/16613685725.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/161357cbbad275---5530582465.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/jakafo.pdfIn PDF document text
    • http://hlqh.net/userfiles/file/20210906030750_2042476743.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gowimigoxasukatusorom.pdfIn PDF document text
    • https://servingltda.com/userfiles/file/86141751230.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/49536949641.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/towiwew.pdfIn PDF document text
    • http://romengo.com/ckfinder/userfiles/files/67128030834.pdfIn PDF document text
    • https://protrialse.eu/files/files/bifejote.pdfIn PDF document text
    • http://lutechmed.com/Images_upload/files/19934895198.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/2650093856.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/7851008707.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_off0000b96d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB96D 16620 bytes
SHA-256: 5c8cf7afe026e9a0d1240595cf12b8c63bf73fc3f3d8b51a5c8ddd6435e4a4be
font_01_sfnt_off0000e40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fc26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC26 10812 bytes
SHA-256: 4c33cc989bab3abef6d9e6b576ca4142d1fd086a720273ca61c8b962c321109c