Malicious PDF — malware analysis report

Static analysis result for SHA-256 21768d7bf325fc98…

MALICIOUS

PDF

84.0 KB Created: 2021-09-17 08:27:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9b39bb7537c0009b530aeb922ce7674b SHA-1: 18217cd20d1ca5c9ca44cebb2f084fb9ede68aac SHA-256: 21768d7bf325fc98908380c574221d5a8d21cccb3be738f1cc51b187c7728e89
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to suspicious PDF files on unknown domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the idea that the document is designed to lead users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://carrozzeriardue.it/userfiles/files/58444767706.pdf In PDF document text
    • http://jadever.vn/Images_upload/files/84465496130.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/42385985509.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/bunutobefod.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/penidimekalojovebedim.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/bevamiragevinuxovamode.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/44987469149.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109062229179980.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/suzodefowonilutodazalen.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/63377998267.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/kigelon.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/depijowaforafemidegezo.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/18951812762.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/66389726172.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce5bf5ef19---62369538822.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/81414742381.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/a0lr3f0lk4piop7p8j1f5h1pqa/xodaweze.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/76711803396.pdfIn PDF document text
    • https://hanedantoptan.com/upload/files/kugujudiniwetakuvizivef.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///14625085701.pdfIn PDF document text
    • http://akconta.com/uploads/files/jijef.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/sikubogeteveximumeji.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/41057462294.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/welokidujesuroraguvonew.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/49064202581.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/41338191455.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=android+turn+on+phone+without+power+buttonPDF 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_off0000e219.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE219 10420 bytes
SHA-256: a961c61c76f390a0c0e1fd42dd8141805e30a0530687ddf284a4cb35373727a2
font_01_sfnt_off0000f96c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF96C 18436 bytes
SHA-256: 29dd850db2b892df0db7a8aec9f2df1a6effcd6a3af332b9d3aec410e50b794e
font_02_sfnt_off00012976.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12976 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1