Malicious PDF — malware analysis report

Static analysis result for SHA-256 20e8069b871d3518…

MALICIOUS

PDF

80.4 KB Created: 2021-03-21 02:05:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: e1c838da307998620e751edfdd22d962 SHA-1: 83c4cd7d49df4dc2ab9c58001e2c415e5529c807 SHA-256: 20e8069b871d351871b44002a16b5c4a46191e20617cf541905485c8db2bf3e1
186 Risk Score

Malware Insights

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

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 0.9995

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 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.
  • 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://kuzutuzo.ru/award?keyword=perimeter+and+area+of+plane+figures+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4462730/normal_6025014a4e88a.pdfIn PDF document text
    • https://texexavif.weebly.com/uploads/1/3/1/4/131454683/8797569.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447888/normal_603b2231934b0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375070/normal_602ffcf17971d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392664/normal_602863a65223a.pdfIn PDF document text
    • https://gakififevorejep.weebly.com/uploads/1/3/1/8/131872199/789123fbeb272ea.pdfIn PDF document text
    • http://tufusojakigun.iblogger.org/jurnal_manfaat_cacing_tanah.pdfIn PDF document text
    • https://nexiwurepefisov.weebly.com/uploads/1/3/4/3/134372078/dorofuzikavo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367311/normal_60300d0874412.pdfIn PDF document text
    • https://guxemufisi.weebly.com/uploads/1/3/2/7/132710659/jowolemelo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mowilutom.epizy.com/lung_cancer_risk_factors.pdfIn PDF document text
    • https://s3.amazonaws.com/xenavuxa/91193274970.pdfIn PDF document text
    • https://s3.amazonaws.com/masevewi/how_many_numbers_in_nc_drivers_license.pdfIn PDF document text
    • https://s3.amazonaws.com/fizufapu/sign_in_sheet_template_google_docs.pdfIn PDF document text
    • http://dudulumunir.epizy.com/javifenurifibatibiveg.pdfIn PDF document text
    • http://zokekoja.rf.gd/93035054226.pdfIn PDF document text
    • https://s3.amazonaws.com/vifusupegiza/31624547810.pdfIn PDF document text
    • http://vipojidetag.epizy.com/kibukomomikiwekubuvet.pdfIn PDF document text
    • https://s3.amazonaws.com/dazutun/world_book_encyclopedia_2016.pdfIn PDF document text
    • http://kiwaxujunexozet.epizy.com/the_apocrypha_and_pseudepigrapha_of_the_old_testament.pdfIn PDF document text
    • http://lekekavom.epizy.com/slader_app_apk.pdfIn PDF document text
    • http://xevikosurozogin.rf.gd/84297636550.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
    • 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_off0000e06e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE06E 5360 bytes
SHA-256: ca266025333d08f9e44af8cf8e32eac85f1f93cc12f26331c8d4cdd18e4737c1
font_01_sfnt_off0000f299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF299 12864 bytes
SHA-256: 8a31af1ee2b23499ec2bb52fd3c6d838020a2084e487dc8457d0202ee56eac24
font_02_sfnt_off00011e75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E75 16224 bytes
SHA-256: 33398f1703d5dea76ae3b0b64029bb59778f6f47ab1ecebd2ec1d0c640162a4e