Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb7b21165f2c1887…

MALICIOUS

PDF

73.9 KB Created: 2021-09-18 06:17:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: dc8f92867a7ef709a2ae2aa48223b38a SHA-1: 713d07df7e46e6c9fd86a3017e994bda8329960e SHA-256: eb7b21165f2c1887a135f5c9ad0063090a837e84b29c8aa8b9fc3aea2277b765
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains embedded JavaScript and numerous external URIs, suggesting it's designed to redirect users to potentially malicious websites. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a link farm on disposable hosting, further supporting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • 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://coretry.ru/uplcv?utm_term=imo+beta+2019+old+version+apk PDF link annotation
    • https://angel-juicer.com/FileData/ckfinder/files/20210914_05F95BEE8E3ABBE2.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/vojewinawuwe.pdfIn PDF document text
    • http://sacmacbook.net/userfiles/file/takewoxuvinanuk.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/86931123579.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/vebozelawewidijakisofap.pdfIn PDF document text
    • https://posh.hr/files/30103152136.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/wamejozimilunudi.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/wuxefutabupanixaxolip.pdfIn PDF document text
    • https://vinacomvietnam.vn/uploads/news_file/45053899817.pdfIn PDF document text
    • https://nic-irq.com/userfiles/files/53965666357.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/151737042383.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/zazudepudepabejigeb.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/vigoxemifenutepovijo.pdfIn PDF document text
    • http://serextion2006.com/js/upload/files/70658715949.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/8542096746.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210903000559.pdfIn PDF document text
    • https://tessuno.com/upload/files/6136ac8fb2017.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/100577899.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/76993416935.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/731950329.pdfIn PDF document text
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/78497858301.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/6032046718.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/7773937558.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/9597491115.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_off0000c070.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC070 15612 bytes
SHA-256: 29d4c99dfe7917e4e95568fa881583bcdeffce7ae615eaa697d54262ef987284
font_01_sfnt_off0000e893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE893 11264 bytes
SHA-256: e214293f9bb1e7d333b669ef57d7d9395ec90b6a9d89dbd0dffdea8519b54517
font_02_sfnt_off000102d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1