Malicious PDF — malware analysis report

Static analysis result for SHA-256 4087a279b7913052…

MALICIOUS

PDF

77.5 KB Created: 2021-05-18 22:19:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 5e61629ad9161ffafe8aa2bbd35653f0 SHA-1: da9dc5f05067ca1317246f78639bd1cea1eaf32a SHA-256: 4087a279b7913052684f5e586ae98ca046e50defa053b7804ddbd4735f002a21
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://resalured.ru/strik?utm_term=regular+and+irregular+verbs+exercises+with+answers+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4500678/normal_605d6c7c96cd8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4527164/normal_602b910e1ccae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384154/normal_603fe0a1caae0.pdfIn PDF document text
    • http://rekararavufi.iblogger.org/mobile_money_in_ghana.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401976/normal_6011e2c29dc38.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4501484/normal_60095d76cad55.pdfIn PDF document text
    • http://xomaweluk.22web.org/82543042761.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371787/normal_5fcaec016a773.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476432/normal_5fd9199adf1ba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420903/normal_60230064a9b8b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387933/normal_5ff5436b82c40.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459922/normal_5fce9751152e4.pdfIn PDF document text
    • http://pazobano.iblogger.org/72474764576.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447089/normal_60148f3d01cfa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426814/normal_606ca8abbc858.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kojajopi.epizy.com/undertale_undyne_theme_sheet_music.pdfIn PDF document text
    • http://bikenuzuxidan.epizy.com/which_mcat_prep_books_are_the_best.pdfIn PDF document text
    • https://s3.amazonaws.com/kiwopusafize/free_project_cost_tracking_template_excel.pdfIn PDF document text
    • http://koguputi.epizy.com/zoology_books_for_bsc_part_2_download.pdfIn PDF document text
    • http://tufexulirepa.epizy.com/nsf_grfp_reviewer_comments_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/wisuw/allelopathy_lab_report.pdfIn PDF document text
    • http://kopajadipovagu.rf.gd/lspdfr_agency_callouts_download.pdfIn PDF document text
    • https://s3.amazonaws.com/debamijizozexo/28267503108.pdfIn PDF document text
    • http://gawusozuf.epizy.com/27683623955.pdfIn PDF document text
    • https://s3.amazonaws.com/wajibile/perfect_english_grammar_zero_conditional_exercise.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3C 5784 bytes
SHA-256: 4a7c2f786af465bdf2f71f76f2e14df7cd8928926835ba94c995e6dc0796e178
font_01_sfnt_off00010203.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10203 11076 bytes
SHA-256: 93e684fc5f6a55bcccd7254717b74c69f4c75e224ce272c42d204c36c58a13cb