Malicious PDF — malware analysis report

Static analysis result for SHA-256 037e28bfbd83bc00…

MALICIOUS

PDF

70.4 KB Created: 2021-09-16 05:07:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: da982cade3d7df19b70fcf5f1f665ef8 SHA-1: def7c14769374d0636614bc019cd5a39521fc943 SHA-256: 037e28bfbd83bc00e9a53f3befaffe5a26886e2570b37362fc2be08bdd3ee9ae
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, suggesting it functions as a link farm designed to redirect users to potentially harmful content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates a malicious intent to distribute links across many disposable hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crysiq.ru/uplcv?utm_term=tharam+padippicha+koodaram+mp3+song+download PDF link annotation
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/53759678756.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210916_78B92C26A74FB1A1.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/22430164807.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16141f26fba8b1---pasenoze.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/58041823967.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/nojiwu.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/4102466501.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/vukerofigobinijesose.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/xebiv.pdfIn PDF document text
    • https://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/21656386014.pdfIn PDF document text
    • https://art4you.sk/editor_uploads/system/files/28419844040.pdfIn PDF document text
    • http://pazarziraat.com/userfiles/file/68974693938.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/ganufusirifimajizaziw.pdfIn PDF document text
    • https://mollis.rs/files/19016779744.pdfIn PDF document text
    • https://edouardweil.com/userfiles/file/jolemonateburulisolef.pdfIn PDF document text
    • http://kelsenator.com/userimages/juzutapixujavabuzarope.pdfIn PDF document text
    • http://media-production.net/admin/ckfinder/userfiles/files/50250758478.pdfIn PDF document text
    • http://qigong.ru/userfiles/file/xetewokipetor.pdfIn PDF document text
    • http://recuva.kr/upload/fck_img/1631740739/file/lapisijepirub.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/92571361389.pdfIn PDF document text
    • http://ekvatorbl.com/userfiles/file/josurerudotowaku.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210906164739.pdfIn PDF document text
    • https://knoxvilleremembers.com/media/guwejuv.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_off0000b248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB248 11044 bytes
SHA-256: ba16b3397af1d7b0c7747e8a229316ed746d4c03023c795944b393238e8b005f
font_01_sfnt_off0000cb9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB9F 15584 bytes
SHA-256: 8a08170cc72df23259e5b38518a58ecf466f8a361c5162e7d3eb6ed5f35bdb85
font_02_sfnt_off0000f3ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1