Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0c366a6a232935f…

MALICIOUS

PDF

72.1 KB Created: 2021-10-01 02:18:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8300690d6772bdae9f146c270f808ecb SHA-1: e39364d719ddd80c91ff6c10dd3488363a186571 SHA-256: f0c366a6a232935f0ee6939f9b653b0b90c7dabd142f2d1b82b2d7eea9a754a1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that function as a link farm, primarily directing users to download-related content, including VPN software. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a pattern of using disposable hosting for these links, suggesting a malicious intent to distribute unwanted or harmful software. The ML classifier and ClamAV detection strongly indicate the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://archism.ru/uplcv?utm_term=snack+vpn+download+free PDF link annotation
    • https://classoft.ro/userfiles/file/katofumosuvemadoguz.pdfIn PDF document text
    • http://youil.org/userData/board/file/48703331343.pdfIn PDF document text
    • http://studioingegneramato.com/userfiles/files/bufazarugijanamidugikozox.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/9095650848.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/54342577255.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/tulakerewasu.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/kiwotesax.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210918_6983CF143E5FDCFC.pdfIn PDF document text
    • http://oumkua.com/userfiles/file/sedusivorikugedugifiwewuv.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/a5t7poqtu2874jl0lu7k43cu4f/bilujolazaza.pdfIn PDF document text
    • http://knipia.com/userfiles/file/35305795581.pdfIn PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/tutidusugigo.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/89943407162.pdfIn PDF document text
    • http://koutingchina.com/upload/files/pamavisanetudigemuwusut.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/6495538614.pdfIn PDF document text
    • http://lube-stc.com/ckfinder/userfiles/files/59278896902.pdfIn PDF document text
    • http://halmar.info/userfiles/file/xavetaxurojifem.pdfIn PDF document text
    • http://studiomistretta.com/userfiles/files/tiwufugina.pdfIn PDF document text
    • https://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/48515333303.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/29351500505.pdfIn PDF document text
    • http://cosmeticdermatologymiamibeach.com/uploads/data/files/77594271639.pdfIn PDF document text
    • https://nppgursaraijhansi.in/ckfinder/userfiles/files/vesukumad.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/92895067597.pdfIn PDF document text
    • http://www.trackls.com/application/ckeditor/ckfinder/userfiles/files/77299382670.pdfIn PDF document text
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/61533084707.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/57137184244.pdfIn PDF document text
    • https://vanchuyensahara.com/site/files/foxereguwebovonutebibu.pdfIn PDF document text
    • http://chamaeleon-produktion.cz/www/files/file/nonovaj.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_off0000b66f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB66F 16632 bytes
SHA-256: 7e60621bbe0217f6d638945a3cccabaddbd8bb4e55cb90fa15d4b02b0e533822
font_01_sfnt_off0000e0df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 10576 bytes
SHA-256: 259e2d7922e3211e0b4a9ea21791450299cb4d3a3d86b78776d39508a6458bbf