Malicious PDF — malware analysis report

Static analysis result for SHA-256 a66e53f9a13a6003…

MALICIOUS

PDF

87.3 KB Created: 2021-09-20 03:48:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9de56c13cf1dd876fc44bac61e2144ba SHA-1: 99233dd4f1b2bb707080c1a7f4d5f3b98c4592bf SHA-256: a66e53f9a13a600346ccc5163d2f04ec10e7f196797c5bbe4d1e8718a0bd36ef
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects to external URLs, as suggested by the PDF_URI and EMBEDDED_URL heuristics, which are often used for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://atrax.hr/files/59049442964.pdf In PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380c6d5db81---5844607672.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/finezukolumi.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/gutawikaxo.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/91704536289.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/67643104280.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/guxasosenurekarogagadegij.pdfIn PDF document text
    • http://www.ishvani.com/www/js/ckfinder/userfiles/files/92862572709.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/36403390214.pdfIn PDF document text
    • http://nhungbaithuocnam.com/img-tvdl/files/86909473932.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/bapimoxidepakewekuzigipuz.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021091417582270.pdfIn PDF document text
    • http://www.scea.edu.mn/ckfinder/userfiles/files/41296423890.pdfIn PDF document text
    • https://teater77.nl/userfiles/file/jutozadimavanumewivorakeg.pdfIn PDF document text
    • https://groupburuemas1.com/contents/files/folok.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/77966808387.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/52675199065.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/54938813701.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/timetuxutime.pdfIn PDF document text
    • https://ajambary.com/userfiles/file/xejuzerubafokinuv.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/fozuruvafaliganalazel.pdfIn PDF document text
    • http://alatasfilms.gr/ILC/img/file/38600864423.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/panebuwitajikasakoxiji.pdfIn PDF document text
    • https://fulzugaskozpont.hu/files/74250413303.pdfIn PDF document text
    • http://www.cavice.fi/tiedostot/files/vojixotemofivekofi.pdfIn PDF document text
    • https://villamishkan.com/310renonew/front/images/files/50122621319.pdfIn PDF document text
    • http://lmtechsolution.com/userfiles/sabojepofutavabedin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+create+menu+bar+in+androidPDF 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_off0000f09d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108AF 17660 bytes
SHA-256: 248fcaf0da67faa7af503cee3f140e7666c5b4781c0f0db150e756cc59874b26
font_02_sfnt_off000136ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136CE 10636 bytes
SHA-256: 137cd491fe6ab1adf6b4898b4fa6961948f16e2413b2c042caddcd902e04859b