Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a275ab69e79f138…

MALICIOUS

PDF

67.0 KB Created: 2021-02-21 19:55:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 0cbf9d85aa693e92d3a6031e7385e0ca SHA-1: 12a12736d2ff31b1e4317aa42b452a50223f1d6e SHA-256: 3a275ab69e79f138fac4413b6004dfa068cfd99906ba02d5253a57cda566afb2
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 0.9998

Heuristics 6

  • 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 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://baarspo.ru/strik?utm_term=how+many+pressure+switches+does+a+furnace+have PDF link annotation
    • https://fevokixesebu.weebly.com/uploads/1/3/0/7/130776230/sefogabosajata.pdfIn PDF document text
    • http://tobufasir.iblogger.org/granularity_definition_in_information_technology.pdfIn PDF document text
    • https://wuzezabor.weebly.com/uploads/1/3/1/4/131438899/bogadaz.pdfIn PDF document text
    • http://naguvogegexaze.22web.org/preschool_letter_h_coloring_sheets.pdfIn PDF document text
    • https://tolajugim.weebly.com/uploads/1/3/4/6/134647220/2f9d03a6db79.pdfIn PDF document text
    • https://tugiwosigef.weebly.com/uploads/1/3/2/7/132740290/fisovajux-lazuxomakipalam.pdfIn PDF document text
    • https://cdn.sqhk.co/zojixemem/cbgdggS/werarepuzegalegop.pdfIn PDF document text
    • https://taxufutusa.weebly.com/uploads/1/3/4/5/134514166/vipuvewunotetebep.pdfIn PDF document text
    • https://mikatafa.weebly.com/uploads/1/3/1/3/131398449/977be3fe7af.pdfIn PDF document text
    • https://sezavifibeka.weebly.com/uploads/1/3/4/4/134463458/4640558.pdfIn PDF document text
    • http://lujakivuvig.22web.org/21990381470.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wewuxuviwar/cien_aos_de_soledad_temas_ap_spanish.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_off0000c842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC842 5580 bytes
SHA-256: 255dac7492f9d92ef39ba9871db8c3b4a261e21aa31515daffb5bb5e66209f0c
font_01_sfnt_off0000db28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB28 10504 bytes
SHA-256: bc697929232d75b375075a6481b217f48269153a36261fbb4a0f3b6c6183c43d