Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fe29689169f9553…

MALICIOUS

PDF

68.5 KB Created: 2021-09-25 12:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a8f44531ae4e4d3dc1a58e3b4618276d SHA-1: 0541e9477d297d0989792b9722afc191f1421a40 SHA-256: 3fe29689169f9553fcea0fa488bcc75d9e11aad3025fffbda84cc7b7538916a1
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests an attempt to distribute malicious content or phish credentials through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 https://777mto.info/contents/files/pubekuvedesijomisazobomu.pdf In PDF document text
    • https://momentous-inst.com/uploads/image/files/44454356667.pdfIn PDF document text
    • http://gd-weimi.com/upfolder/e/files/20210906185542.pdfIn PDF document text
    • http://castel.lu/userfiles/files/74779115791.pdfIn PDF document text
    • https://stealthwindow.tw/uploads/files/202109121524412313.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/32714707999.pdfIn PDF document text
    • https://cuatudongsaigon.vn/uploads/files/nibidovajexol.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/mna98e8rfbtabunot2l1h179v7/24106000740.pdfIn PDF document text
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/17247204640.pdfIn PDF document text
    • http://greenglobepms.com/uploads/59024527583.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/f448116756609f7038a2dd00c7061f72/kupoge.pdfIn PDF document text
    • http://arredamentoambienti.it/img/file/tazifubenekunororisojixog.pdfIn PDF document text
    • http://zmz72.ru/files/file/41683663859.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/13954063106.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/gikavenuwufa.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16143e3019c10e---kevazanudirowogimozamaj.pdfIn PDF document text
    • https://atrax.hr/files/ginugakodomudi.pdfIn PDF document text
    • http://solee.cn/ckfinder/userfiles/files/favobi.pdfIn PDF document text
    • http://asvpp.fr/pdf/93102938587.pdfIn PDF document text
    • https://tedvandergulik.nl/userimages/file/75313587575.pdfIn PDF document text
    • http://prestinoequitacion.com/imagenes/upload/files/1917828447.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/pibagujo.pdfIn PDF document text
    • http://egyptlance.com/userfiles/file/tisurijiriziximapiwebu.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/dadawekabilegosa.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/jolaxinijamatineputoka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=apk+feed+and+grow+fishPDF 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_off0000b03e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB03E 10792 bytes
SHA-256: 79f57fd56ba7c0dc0b354db7ba6642bd6bdc1eb5b7f29637a3d079fa76dc0004
font_01_sfnt_off0000c8f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE102 14280 bytes
SHA-256: bd451a6df0827f3c86abdffc8bf798079e214d3fd344d9fa892b0a8f8d325417