Malicious PDF — malware analysis report

Static analysis result for SHA-256 76bd8785de06b7ab…

MALICIOUS

PDF

75.9 KB Created: 2021-02-10 17:26:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: dba801534b07495bdb94bd72719a9b90 SHA-1: 6d44b24364f27cb454e59687856f77a754d4847a SHA-256: 76bd8785de06b7abc03e1887b0eb23484e100cbad19c12224aaa60b9e4202ac7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URL pointing to 'jacksth.ru', which is likely part of a phishing or malware distribution scheme. The document body, though heavily obfuscated, suggests a lure related to a markdown cheatsheet.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jacksth.ru/aws?utm_term=markdown+cheatsheet+md PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4385617/normal_6000d374d2a97.pdfIn PDF document text
    • https://cdn.sqhk.co/mujutuzidip/le1ihie/desktop_tower_defense_strategy.pdfIn PDF document text
    • https://cdn.sqhk.co/jepivitixiwo/h9eJUia/76778974580.pdfIn PDF document text
    • http://profer-opt.ru/6826085444spy89.pdfIn PDF document text
    • http://mishabelle.ru/semijegoxizedj9wkw.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415742/normal_5fc9321b0338a.pdfIn PDF document text
    • http://begdas.space/401924602272n76n.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421612/normal_5fe7e5da38803.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375703/normal_5fe75b01dc0c7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gubuker.epizy.com/idsa_guidelines_uti_2017.pdfIn PDF document text
    • http://boxalage.epizy.com/alfa_romeo_156_performance_parts.pdfIn PDF document text
    • https://s3.amazonaws.com/wulotugadag/html_to_php_free.pdfIn PDF document text
    • https://s3.amazonaws.com/towutoginadivu/danulenawuvopivedumalopap.pdfIn PDF document text
    • https://s3.amazonaws.com/juzowilipi/51781637681.pdfIn PDF document text
    • https://s3.amazonaws.com/tedowafomaru/mogor.pdfIn PDF document text
    • https://s3.amazonaws.com/fizup/62933340047.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFCE 5308 bytes
SHA-256: 2b88a1c80b1567cd90bc22445834b2217508e8c1b2ab981ab1b46b4352627edc
font_01_sfnt_off0000f1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1C6 2208 bytes
SHA-256: 473f3103e51cafbf74fc4179b3cb3851544fce5f6ec2e89452d90f2bdbd086a6
font_02_sfnt_off0000fbca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBCA 11112 bytes
SHA-256: e51d96f8b9991a9613f29cc7d4c20b14e787fdd633a55a6cddca06ff7693d6b6