Malicious PDF — malware analysis report

Static analysis result for SHA-256 39f4f6de2eaf0608…

MALICIOUS

PDF

95.0 KB Created: 2021-09-16 11:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 7767b1797191167d565f7c647f110650 SHA-1: 1004e80a520684b6a77b2d382009d33b3f606e4e SHA-256: 39f4f6de2eaf0608459cde9f8aa15eced1c872489fefe99c6bb7568370288254
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this by indicating the PDF is a link farm on disposable hosting, likely to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/kinalawijezefulave.pdf In PDF document text
    • http://baby-daycare.com/uploads/files/202109031357083761.pdfIn PDF document text
    • https://arendic.cl/files/96639249104.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/78374347632.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/27161750182.pdfIn PDF document text
    • http://cdkuysuujk.handysociality.com/upload/files/tiritutoxakop.pdfIn PDF document text
    • http://hfnhsw.com/upload/files/juzejegimugu.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/52054747365.pdfIn PDF document text
    • https://shatalarab-llc.net/userfiles/files/52435063653.pdfIn PDF document text
    • https://fleseriuassociates.ro/files/file/42116041680.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614259c896c7e---54045621124.pdfIn PDF document text
    • http://www.medic-pneumolog.ro/fisiere/file/61676880669.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/zawigavikifudepujov.pdfIn PDF document text
    • http://cl-pub.com/files/files/96564478358.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/lozibijaxovejabef.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/8d0b4f634837b6c24ac37a891d52bd55/55923439565.pdfIn PDF document text
    • http://webspace.mysdam.net/images/newsletter/files/78200224614.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/wufumadazig.pdfIn PDF document text
    • https://www.borzabadi.com/ckfinder/userfiles/files/73872151877.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/82759562286.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/24722678970.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/dixuxubisoniriban.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/14303358564.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/20219537327707.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=android+mailto+err_unknown_url_schemePDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE533 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD45 25640 bytes
SHA-256: c19fd12303e5aed0303e574a21486f29d9b8b7ce2bfa510d29e1710df29539de
font_02_sfnt_off00013cf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CF2 10928 bytes
SHA-256: a84f110b2ba614dbcb730318c024f447289863147f73c466de0922551376b5c1
font_03_sfnt_off00015625.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15625 16616 bytes
SHA-256: 1e6e3e995169c23382956306f894d114b074b1902afe097d7b0dff5afb7c2655