Malicious PDF — malware analysis report

Static analysis result for SHA-256 b883edc67518c214…

MALICIOUS

PDF

74.2 KB Created: 2021-02-05 18:59:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: fe173e347033c40e50151e958c8ef04f SHA-1: 4f8e87e50200d9d6f918f8f8fb9b90565e5623e0 SHA-256: b883edc67518c214423da5aadefabf8e1a901727ac0dd121411e204d59e734de
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, pointing to various PDF files hosted on disposable domains. This behavior is indicative of SEO spam or a distribution mechanism for further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, and the PDF_SEO_LINK_FARM heuristic confirms the presence of a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://maypoin.ru/123?utm_term=the+birds+storyboard PDF link annotation
    • http://help-verification.com/kudarakonoxbq2e.pdfIn PDF document text
    • https://cdn.sqhk.co/rasepotobami/rjdhcje/wobofotizesodubebone.pdfIn PDF document text
    • https://cdn.sqhk.co/lanumakefu/bijpibv/age_of_history_2_cheats.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367279/normal_600de0a7ef4e3.pdfIn PDF document text
    • https://wilulesutazi.weebly.com/uploads/1/3/3/9/133997377/f759f7c50.pdfIn PDF document text
    • http://damvglaz0.xyz/hidden_object_pictures_freeu2h91.pdfIn PDF document text
    • https://cdn.sqhk.co/famuxina/jg74hhj/scanmaster_for_elm327_obd2_scantool_full.pdfIn PDF document text
    • https://cdn.sqhk.co/lafuwexale/gjiehh1/siresozofufines.pdfIn PDF document text
    • http://hookup153.online/94893201073g26lm.pdfIn PDF document text
    • http://aromaita.space/fundamentals_of_engineering_economics_and_decision_analysisc4t8j.pdfIn PDF document text
    • https://cdn.sqhk.co/vetukalujir/egfu1jj/pirate_king_hack_tool_no_survey.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495994/normal_5fd3ad3bd7f4c.pdfIn PDF document text
    • https://wowujisalot.weebly.com/uploads/1/3/4/3/134349860/lobezopibuj_fedisi_gotego.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417314/normal_5fed3012b2174.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000e714.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE714 5072 bytes
SHA-256: 341096c6e144f9469da2cbe60d720037baf6e71853d079d67ad1e1e3a253a5a7
font_01_sfnt_off0000f849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF849 10452 bytes
SHA-256: 5839f5b82ca92c6fc7525856d7db2045ac003044309f8e1212cb68fa9c608027