Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb4ec398ba762111…

MALICIOUS

PDF

75.7 KB Created: 2021-03-10 10:17:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dbc8a366648e600f21fb4cbdf2b4de70 SHA-1: 98150d5159da2060f49845502828317c87cfc7af SHA-256: fb4ec398ba7621110321806fa34312f9222e2d74d3965e63c4b3be1c6c156c3a
156 Risk Score

Malware Insights

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

The PDF file contains heuristics indicating it is a phishing document and hosts a large number of external links, many of which are likely part of a link farm. The primary malicious URL identified is 'https://xezojetit.ru/123?utm_term=happy+birthday+song+in+korean+informal', which is presented in a deceptive manner within the document body. While no scripts were explicitly extracted, the PDF structure and the presence of external links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://xezojetit.ru/123?utm_term=happy+birthday+song+in+korean+informal
    • https://fabisinutufonos.weebly.com/uploads/1/3/5/9/135993578/6126423.pdf
    • https://fedalovojuxunod.weebly.com/uploads/1/3/0/7/130775560/d3caf.pdf
    • https://nizevamil.weebly.com/uploads/1/3/2/8/132814567/jipil.pdf
    • https://gerugufudob.weebly.com/uploads/1/3/4/8/134869234/8969559.pdf
    • https://jugivukovetid.weebly.com/uploads/1/3/0/7/130739525/69018e9c1c4c0c.pdf
    • https://wawokosekipazas.weebly.com/uploads/1/3/1/4/131452886/886171.pdf
    • https://tajidirubizev.weebly.com/uploads/1/3/0/7/130739153/puwusobaxezuka.pdf
    • https://firulozide.weebly.com/uploads/1/3/0/7/130775295/newefinof.pdf
    • https://wosowabo.weebly.com/uploads/1/3/4/3/134340570/6ab64a511.pdf
    • https://faremuxonebaw.weebly.com/uploads/1/3/4/5/134598019/b674037b9b522.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/bokofapig/microsoft_excel_duplicate_sheet.pdf
    • https://uploads.strikinglycdn.com/files/a2a8610d-e2ca-4afb-8128-668b2964d408/5719726825.pdf
    • https://s3.amazonaws.com/ropuba/redagudusopif.pdf
    • https://s3.amazonaws.com/gumagabu/15824297155.pdf
    • https://uploads.strikinglycdn.com/files/158fc675-0d89-4cfb-ad2d-6ee0cb609a6c/5906612766.pdf
    • https://s3.amazonaws.com/zodererezuzuxi/fugudamatetiruruzasiv.pdf
    • https://506dbbd1-d4b3-44b1-a4c9-6b5d0cab6a23.filesusr.com/ugd/c75f60_e52583294e834e5a963b736d6f707d24.pdf?index=true
    • https://uploads.strikinglycdn.com/files/61a52cf9-8152-493f-9652-296badce45b8/wipexuposefudomenines.pdf
    • https://s3.amazonaws.com/kodipopujufipig/budget_math_worksheets_free.pdf
    • https://s3.amazonaws.com/xapijifas/81514466342.pdf
    • https://510adc33-753b-44c0-977e-8d34da8fcdd4.filesusr.com/ugd/5f4192_811aa68ddf3844388fbad7e0aea1db2c.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea65.bin
772bc8be5d4ad58f917e42e961e5aeed5b1baa66097fd06f55c5740ee4896c53
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA65 5720 bytes
font_01_sfnt_off0000fdb0.bin
f66f633800c5e811b6d4434cc8e01372b8e9516ad5f5997f037a9e7b43ab73d2
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB0 10592 bytes