Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b55a6690c434b3e…

MALICIOUS

PDF

92.0 KB Created: 2021-09-19 20:45:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 47de04708e5d9384d6ae5c8c56fdba70 SHA-1: 63b7da79752915a11df1950714b257f1ebc32894 SHA-256: 3b55a6690c434b3e8a1cb6f223afff5cffe282e6077332c21e715bd2b323b274
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users to potentially harmful content. The presence of these link farms and the overall structure suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://vhktn.at/images/content/files/8222908330.pdf In PDF document text
    • http://thaisomboonautopart.com/userfiles/files/47311472506.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/gusenukireru.pdfIn PDF document text
    • http://longvu.vn/Images_upload/files/davofekuvepazi.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/niraxuximawumejeborad.pdfIn PDF document text
    • http://besttailor.info/ckfinder/userfiles/files/siwizu.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/17987383840.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/c5c18c376894d4a145ac8a07fef058b9/mowawudun.pdfIn PDF document text
    • http://thechelseaff.com/user_uploads/files/lujakus.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/f16d8f38da883a8c2c8d1cdf19409704/pikijavuletiwuvamus.pdfIn PDF document text
    • http://sevoir.hu/uploads/file/minatiwosujajirugakagulu.pdfIn PDF document text
    • https://divinenine.net/userfiles/file/xejalupimobugonuwod.pdfIn PDF document text
    • http://exima.kr/userData/board/file/65406417671.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/95k0onfl56lsbcmmun9kh8amcc/bamerinivomumut.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/vunovexodejokux.pdfIn PDF document text
    • http://perevodvnegiloifond.ru/pict/file/xomojeti.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/fmed5uesngr6pdfv1h82531rrc/86964745842.pdfIn PDF document text
    • http://zangerlelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/naxinidov.pdfIn PDF document text
    • http://ellev.fr/upload/files/98959551276.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/4180197727.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=free+among+us+online+playPDF 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_off0001011d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1011D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011934.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11934 10688 bytes
SHA-256: d687f17f37b9e488a6b2c6d88e54dc4f4c2fe0541d4e86ed45db710e20599873
font_02_sfnt_off000131a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131A2 18896 bytes
SHA-256: 890c82bc11fdf32422732cc2c487d96576cc8824dd0fd9c4f53b8f3118cffbea