Malicious PDF — malware analysis report

Static analysis result for SHA-256 0aa6d8cfc6ce918e…

MALICIOUS

PDF

76.6 KB Created: 2021-09-23 12:52:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 74ffddde528fd1d8b6859e45341ef328 SHA-1: 2a42c355fb7f39ca3e83a3ca6e65ea0e78129b45 SHA-256: 0aa6d8cfc6ce918e2cbb3e166d84ff57656d8fbd038ab94cb915863936a33747
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to disposable domains, a common tactic for link farms used to distribute malware or conduct phishing. Heuristics indicate it's a link farm on disposable hosting, and ClamAV detected it as a phishing trojan. The ML classifier also flagged it with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://crewmak.ru/uplcv?utm_term=fundamental+physics+o+level+pdf PDF link annotation
    • http://oookub.ru/upload/fckeditor/file/73409473545.pdfIn PDF document text
    • http://lamorenj.com/userfiles/file/13430616357.pdfIn PDF document text
    • https://mytopics.it/uploads/file/31697679798.pdfIn PDF document text
    • http://vidol.eu/userfiles/file/jobitoliletowefi.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/34681328119.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/81791344404.pdfIn PDF document text
    • http://artanuji.ge/admin/ckeditor/ckfinder/userfiles/files/97245888140.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145755215034---pofigajebuz.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/belavasobukesafusa.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/jubolunilutefunib.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/mebeduxunisi.pdfIn PDF document text
    • https://playerpress.com/ckfinder/userfiles/files/bejoku.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/22348672488.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/54232564884.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/gojaboxefum.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/51667070014.pdfIn PDF document text
    • http://a-mega.ua/images/uploads/file/10217781202.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/nixorarirejokaji.pdfIn PDF document text
    • http://kht.civilkozpont.hu/uploads/file/19034247882.pdfIn PDF document text
    • http://xn----7sbbbizu2bxaod.xn--p1ai/userfiles/file/13889462470.pdfIn PDF document text
    • https://brukspec.pl/upload/file/4521063351.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/tupexazozujix.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/65227867143.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/79849493687.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/75008050368.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/70990111880.pdfIn PDF document text
    • 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_off0000c5d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5D7 11044 bytes
SHA-256: a5e76bba136467656cfea0c737efb65c79b06cbe87164e1d89ddf6620ad13f68
font_01_sfnt_off0000df5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5E 17444 bytes
SHA-256: 3e18d9e85ae77700a38ffd02f873714d85fbe0a84f3c7cd49747cb93625fd922
font_02_sfnt_off00010c7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1