Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a185a600a91b2e…

MALICIOUS

PDF

70.9 KB Created: 2021-09-09 07:33:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 5747cf7fe3ac43a003aff6bd6222f961 SHA-1: 264713489f43ff7b91bcaace4ed6383b7c813ba6 SHA-256: 88a185a600a91b2e28f42ba0ab5bfe8bff5eb4e1935fe0c0850d58df8161b63a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier with high confidence. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies this pattern. While no scripts were explicitly extracted, the nature of the embedded URLs suggests an intent to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://rjpexport.com/files/62423869416.pdf In PDF document text
    • https://chmelo.hu/sites/default/files/file/74532051806.pdfIn PDF document text
    • http://gsprojekt.eu/userfiles/files/danovuvotuganuzilemu.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/kazofuluzexo.pdfIn PDF document text
    • https://manualismedicina.hu/fileok/file/55020425976.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/58805857904.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/supawelu.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/marorululif.pdfIn PDF document text
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/tijekojibilodexi.pdfIn PDF document text
    • http://hejia-ele.net/upload/50516744542.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/soloruto.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/xufobeluxubobugev.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/86632859874.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/a14bea428f9f19340a8935e28b253900/89695849532.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/suroru.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/lumamokinufipof.pdfIn PDF document text
    • http://energosol.pl/images_cms/file/didasala.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/27938864054.pdfIn PDF document text
    • http://imssp.by/data/images/fxeditor/file/50789524060.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/vebub.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/zaruluduzagadusewete.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/81852792623.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/15044834915.pdfIn PDF document text
    • http://www.salpasafarit.fi/tiedostot/files/savudijurunurikosodafel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=best+free+pdf+reader+for+windows+10+2020PDF 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_off0000b399.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB399 16004 bytes
SHA-256: 0094f1e80af0c53dc65a1393d194ae4cfae579c5f309f1e3fcbfc0a604a33cea
font_01_sfnt_off0000dc69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC69 10880 bytes
SHA-256: a9f8805851376a1095baa7a0a86538821f9c38ff6e65e06a3979b2ef63f335b0
font_02_sfnt_off0000f5db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1