Malicious PDF — malware analysis report

Static analysis result for SHA-256 e719c04301e265c8…

MALICIOUS

PDF

81.2 KB Created: 2021-09-15 15:14:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 977cf0d034475d88d97790a9d835f2a0 SHA-1: a85f0762e82c5113f02a404d8d105ed1fad044a1 SHA-256: e719c04301e265c8a3a8965ebebd4a654b0186632d3116da7b7bc20c812008e6
142 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The embedded JavaScript stream and numerous external URIs suggest an attempt to download and execute a second-stage payload, likely exploiting a vulnerability for client execution. The presence of a visual download button further supports a phishing or social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=duolingo+apk+download PDF link annotation
    • http://bushurov.ru/images/files/zidozademeruvifenajita.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/57915250738.pdfIn PDF document text
    • http://minhquoc.vn/ckfinder/userfiles/files/redirokiwazikazev.pdfIn PDF document text
    • https://sindonis.com/userfiles/file/jofamuluxakutixuzezevexoj.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/tonudoburenadoxapuz.pdfIn PDF document text
    • https://gruppopolidori.com/upload/image/file/87117611061.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16131aeec23448---50864598058.pdfIn PDF document text
    • https://jdsliquorlocker.com/nbloom/fckuploads/file/88012050043.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/55112271166.pdfIn PDF document text
    • https://cooperadora.grupocreartel.com/documentos/archivos/22110687700.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/mivanomasefegepa.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/19164110666.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/10534422595.pdfIn PDF document text
    • https://ldoris.com/upfile/files/20210908010831.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/58686956134.pdfIn PDF document text
    • http://saddabro.com/userfiles/file/53935438999.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/7676966034.pdfIn PDF document text
    • http://uptownchantilly.com/uploads/files/fedozesazudoledupamojinaw.pdfIn PDF document text
    • http://tufaghanafc.com/js/ckfinder/userfiles/files/80474294411.pdfIn PDF document text
    • https://mccartha-cobb.com/userfiles/files/33191773438.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/jopupizomikanolelemerikug.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/lefezibaguzoraledovizozi.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/1118607510.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/ledavobilelawagatumok.pdfIn PDF document text
    • http://lejuriste.ru/files/file/joxugofuk.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/lujefir.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_off0000d9ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AC 10348 bytes
SHA-256: 454101e252266f51e46dbb710cbc206e982b553644b1521988369d7074b3957c
font_01_sfnt_off0000f0de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DE 17736 bytes
SHA-256: ff02adde81f10dab65890d3c886266b6a598e1358b098b32afa9d79dc757c0c4
font_02_sfnt_off00011ee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1