Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6c092ecdf153437…

MALICIOUS

PDF

81.3 KB Created: 2021-09-10 20:08:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c0cf8a0b61974c6b9551a4e1e3b794dd SHA-1: 51fef18a09a49782af10c918e191688826576c66 SHA-256: c6c092ecdf15343756595b3162db0e7c9203fd9a5c93803e5df51d4e710b7f86
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The presence of embedded JavaScript and a large number of external links, many pointing to PDF files on unknown domains, strongly suggests a phishing or malware distribution attempt. The document body was unreadable, but the heuristics indicate a link farm strategy, likely to obscure the ultimate malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://rainbowfurnitures.com/files/files/gexesuveg.pdf In PDF document text
    • https://sieuviet.net/webroot/img/files/21964149933.pdfIn PDF document text
    • http://chanhungcorp.com/images/uploads/files/64492733005.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/72115055564.pdfIn PDF document text
    • http://snp-ent.com/files/fckeditor/file/3372322686132999e8b731.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/49797169434.pdfIn PDF document text
    • http://www.petercar0937494634.com/upload/img/files/vavumoxita.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/jomogobimisuboto.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210905073430.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/15166748540.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/miranolonubof.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/wetidajotav.pdfIn PDF document text
    • https://trexanh.net/upload/files/50181321474.pdfIn PDF document text
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/77996094617.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/nagivotu.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210901152304.pdfIn PDF document text
    • http://bamor.org/userfiles/file/48417951937.pdfIn PDF document text
    • https://pointwebhost.com/calisma2/files/uploads/86658280728.pdfIn PDF document text
    • https://ntpuvoice.com/ckfinder/userfiles/files/nidaxuzapobanu.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/xikinotobapekajodigedu.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/tapepotibakefu.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/xilinexuvokofu.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/73843791571.pdfIn PDF document text
    • http://geodez.com/pliki/file/52882504542.pdfIn PDF document text
    • http://sirinthepgroup.com/userfiles/file/filek.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/33994279608.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612faa5f6baa0---nutixev.pdfIn PDF document text
    • http://thrifthelp.com/flash/thrifthelp.com/file/46079267540.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=redmi+9+prime+settings+menuPDF 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_off0000d844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD844 17980 bytes
SHA-256: de1986f6acb0df57f27c34222b80c524b71e59eeb0902f3bf4e05dfa5cf4e3ce
font_01_sfnt_off00010702.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10702 10720 bytes
SHA-256: 7246a00fd9d6db3a24e46d6a5e05a80e872d31449f00e9a4ae3d0bef68fa621a
font_02_sfnt_off00011f6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1