Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce351f2e0f1c424e…

MALICIOUS

PDF

75.2 KB Created: 2021-09-22 14:10:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: affaa2d73f08202e7bdb7afb7802e19f SHA-1: 785a88a1044329106f13b4a879f43d4ab4534d03 SHA-256: ce351f2e0f1c424ee4e3d3706ab96b599e6d9dd1440831a61ad92ad48ed281ae
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to other PDF files hosted on potentially disposable domains, indicating a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a tactic to evade detection or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://gma.ge/admin/ckeditor/ckfinder/userfiles/files/45456371452.pdf In PDF document text
    • https://whereestar.com/marinarubicon/admin/file/fatedepu.pdfIn PDF document text
    • https://fivetc.vn/uploads/files/77510425377.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/vajutijumejokowirag.pdfIn PDF document text
    • https://soccerauquebec.com/userfiles/file/tazif.pdfIn PDF document text
    • https://huangs.tw/uploads/files/202109131732355952.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/zudamonalenuvu.pdfIn PDF document text
    • https://norservis.com/files/files/nopawalivaj.pdfIn PDF document text
    • https://lwim-ouargla.dz/ar/files/13167548670.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/niropisotuwoxip.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/lobixijituse.pdfIn PDF document text
    • http://izr.fr/files/10853371476.pdfIn PDF document text
    • https://arrad.ch/modules/ck/ckfinder/userfiles/files/55334091288.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/jirejorebamamegi.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/2938639339.pdfIn PDF document text
    • https://jamuiboe.com/webroot/upload_media/5920676951.pdfIn PDF document text
    • http://alrehabourhome.com/userfiles/files/pubesubowawagaxa.pdfIn PDF document text
    • http://byecook.com/ckupload/files/91523110542.pdfIn PDF document text
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/negatitovojiwiwabo.pdfIn PDF document text
    • http://mobilenmr.com/files/files/9437560033.pdfIn PDF document text
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/17123015924.pdfIn PDF document text
    • http://irina-beha.com/ckfinder/userfiles/files/16205595406.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/linisalokudekojirun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=agg+att+koka+keharPDF 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_off0000c655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC655 16548 bytes
SHA-256: d6daf15fdf19992ff7c82e659a2e65334d83731405672fe3dde65e1bd3ad7d93
font_01_sfnt_off0000f153.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF153 10048 bytes
SHA-256: 3683065e882bff6a8395a28704b54a7544059433a77c16a995bcfd702a2f5b49
font_02_sfnt_off000107e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1