Malicious PDF — malware analysis report

Static analysis result for SHA-256 731afbd7eee71d72…

MALICIOUS

PDF

78.9 KB Created: 2020-11-28 01:21:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 63f2c9ab6d5ac0c55e88feed7a0df232 SHA-1: 90f5735bc5fb1c5395fd2db7d1a1df192686beff SHA-256: 731afbd7eee71d7278c255fd145af4f192d32e0a459a362a37558f1d2058bc65
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a fake browser/software-install lure. 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 7

  • 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.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://traffnew.ru/aws?utm_term=mozilla+firefox+browser+exe PDF link annotation
    • https://kilejotiwig.weebly.com/uploads/1/3/1/4/131406519/vugofavezele-lexupiraroz.pdfIn PDF document text
    • https://tivakoxidedopa.weebly.com/uploads/1/3/0/7/130776298/6521306.pdfIn PDF document text
    • https://lugonuwazufat.weebly.com/uploads/1/3/4/6/134673331/34b5315ae.pdfIn PDF document text
    • https://kufazijofiw.weebly.com/uploads/1/3/0/7/130776126/58918fba22b06a.pdfIn PDF document text
    • https://muwigoxafom.weebly.com/uploads/1/3/4/8/134869335/4b5bd60122.pdfIn PDF document text
    • https://dofikusoru.weebly.com/uploads/1/3/4/4/134472045/f092aba37e.pdfIn PDF document text
    • https://vufepuxo.weebly.com/uploads/1/3/4/5/134522835/5def1349c2c2d.pdfIn PDF document text
    • https://bejutiluji.weebly.com/uploads/1/3/4/4/134493367/7509398.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/2aab576b-37fc-4863-b0eb-3fe5b7ebfa60/xexifidiliw.pdfIn PDF document text
    • https://s3.amazonaws.com/vedexajawo/change_text_colour.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f5857505-20a2-44b7-ac46-babd2fbb6046/juvowilivipuvuxagamupezij.pdfIn PDF document text
    • https://s3.amazonaws.com/sugosubexez/where_do_prostitutes_hang_out_in_dc.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/86339e7b-ee2a-4d33-924c-c2a457abed7f/nuzojofolimukevobi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6bb33d43-eff7-44ca-a153-993c600c8bbb/jim_crow_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ecb82b02-0926-4ef2-8db7-c07ecd9fa334/superstar_sm_apk_download.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_off0000d932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD932 5116 bytes
SHA-256: 73b216c2bef17338ecf9d03acb2447afb55a7c38d44228b82951df061006b9aa
font_01_sfnt_off0000ead7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD7 14948 bytes
SHA-256: 46a196c143cfc01901259a372f5f014608f93dc432bc63d1e1a1f417cfb18044
font_02_sfnt_off0001199e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1199E 16096 bytes
SHA-256: 292b67320f20e7e38814323bff47001ccb55b5eebb397aea8a254f3e91f57b87