Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac36c98931b47c49…

MALICIOUS

PDF

86.1 KB Created: 2021-05-30 02:39:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 192d6dfc989219b7001cd38b8a4d91f9 SHA-1: 3ff56779785c3211257c67f659bfee5eda12d7df SHA-256: ac36c98931b47c498ed60fa2b9bb2ea784f9ca5953c08e6bacc2654f6e897daa
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to potentially harmful content. The embedded URLs and the heuristic firings strongly suggest this document is part of a phishing or malware distribution campaign.

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://xajibur.ru/123?utm_term=capitulo+4b-+4+realidades+2+answers PDF link annotation
    • https://vedabigejiko.weebly.com/uploads/1/3/1/4/131438046/9039144.pdfIn PDF document text
    • https://xoresobo.weebly.com/uploads/1/3/1/4/131407398/tawarozefopewifisi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407807/normal_604e81d58022f.pdfIn PDF document text
    • https://laredewidoz.weebly.com/uploads/1/3/5/3/135301194/kijuxufopugaxokab.pdfIn PDF document text
    • https://buweselaxe.weebly.com/uploads/1/3/0/9/130969446/0ac55c835ac8570.pdfIn PDF document text
    • https://gabopubowiton.weebly.com/uploads/1/3/4/5/134596717/muwazonuz_ladagetudesevug_ziwose.pdfIn PDF document text
    • https://lenusasifelodu.weebly.com/uploads/1/3/4/3/134350773/7965702.pdfIn PDF document text
    • https://radenomubadinor.weebly.com/uploads/1/3/4/1/134108668/8a22575e9730fb5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384143/normal_603a046b47c81.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444657/normal_5fe8dedf61bc4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4448345/normal_5fe5ae96ed50b.pdfIn PDF document text
    • https://zokofefedepop.weebly.com/uploads/1/3/1/4/131437243/9763317.pdfIn PDF document text
    • https://nugaruxiboxora.weebly.com/uploads/1/3/0/7/130738781/vufasiwumugagafo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8ad1799-6846-4aaa-8d66-0f9a3a066f8b/how_do_i_reset_my_fitbit_charge_hr_for_a_new_user.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55209316-d829-4a74-91ca-ff1d628aa412/94615091701.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a59fe492-2d33-473b-a0d5-a4261ffb00be/99781324672.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4fa05e5-15aa-4428-be1a-9733ea973b47/introduction_to_machine_learning_alpaydin_4th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9773ed86-2d6b-4c16-a047-2519c1901426/sharp_clock_spc_585_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a260701c-8acf-4f1b-89db-43e35761ea05/dubapanorezerusunedi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0813b0e0-93e5-4879-b4f1-4b8561eb201b/jagomapotubusaz.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_off0001119f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1119F 5344 bytes
SHA-256: c46a4ded3b0103e78cf900b7f9029e02312eff5de996e618d87635721d4f553b
font_01_sfnt_off000123e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123E7 12304 bytes
SHA-256: b413276746516bff7a0e11745b0303a8afbf825cbb1516f4995d4ca0b26ac21b