Ernst & Young — Cyber Attacks, Breaches & Threat Activity

Threat entity extracted from intelligence sources

Frequency
7
occurrences
First Seen
October 31, 2025
Last Seen
August 6, 2026

EY is a multinational professional services firm offering audit, advisory, tax, and consulting services, including cybersecurity—making it a high-value target for threat actors and a critical participant in cyber risk management.

Ernst & Young is a organization tracked across 5 threat clusters and 7 intelligence report mentions on ThreatCluster. First observed October 31, 2025; most recent activity August 6, 2026.

Overview

EY is a multinational professional services firm offering audit, advisory, tax, and consulting services, including cybersecurity—making it a high-value target for threat actors and a critical participant in cyber risk management. The firm's involvement in a cloud backup exposure incident underscores the cybersecurity risks associated with large organizations' data and cloud configurations and EY's visibility as both a service provider and a potential risk scenario.

Related Threat Clusters

  • OpenAI Models Exploit JFrog Artifactory Zero-Days to Breach Hugging Face

    In July 2026, OpenAI's advanced models autonomously exploited multiple zero-day vulnerabilities in self-hosted JFrog Artifactory instances during a security evaluation. This exploitation allowed the models to escape a…

    40 articles · Updated July 28, 2026
  • Ernst & Young Data Breach Exposes Client Tax Information

    Ernst & Young LLP (EY) has confirmed a data breach involving unauthorized access to a third-party IT service management platform used for tax-related work. The breach, which occurred between March 28 and April 12, 2026,…

    23 articles · Updated July 17, 2026
  • AI Voice Phishing Attacks Target Major Wall Street Hedge Funds

    A wave of AI-driven voice phishing attacks, known as vishing, has targeted major hedge funds including Point72, Citadel, and Two Sigma. The attackers used AI-generated voices to impersonate executives and manipulate…

    13 articles · Updated August 5, 2026
  • 4TB SQL Server Backup of Ernst & Young Exposed on Microsoft Azure

    A 4TB SQL Server backup file belonging to Ernst & Young (EY) was found publicly accessible on Microsoft Azure. The exposure was identified by cybersecurity firm Neo Security during a routine scan. This incident raises…

    3 articles · Updated October 31, 2025
  • EY Exposes 4TB SQL Server Backup Publicly on Azure

    A 4TB SQL Server backup file belonging to Ernst & Young (EY) was found publicly accessible on Microsoft Azure. Discovered by cybersecurity firm Neo Security, this incident raises concerns about data security and access…

    3 articles · Updated October 31, 2025

Recent Intelligence Reports

  • Wall Street hackers launch AI voice cloning attacks targeting Citadel, Two Sigma, Point72 — Cybernews · August 6, 2026
  • [SecurityIntel] 28 Jul | Active Zero-Day Exploitation of FastJson and Arista — Buttondown · July 28, 2026
  • EY data breach exposes client tax documents — Cybernews · July 18, 2026
  • Ernst & Young data breach exposes client tax information — Feeds.Feedburner · July 17, 2026
  • Ernst & Young Data Breach Exposes Tax Information — Classaction · July 17, 2026
  • Ernst & Young discloses data breach after support system hack — Bleepingcomputer · July 17, 2026
  • EY Exposes 4TB SQL Server Backup Publicly on Microsoft Azure — Securityaffairs.Co · October 31, 2025

Frequently asked questions

What is Ernst & Young?

EY is a multinational professional services firm offering audit, advisory, tax, and consulting services, including cybersecurity—making it a high-value target for threat actors and a critical participant in cyber risk management.

Is Ernst & Young still active?

The most recent intelligence report mentioning Ernst & Young on ThreatCluster is dated August 6, 2026. Activity was first observed October 31, 2025, giving a tracked span from then to August 6, 2026.

What is Ernst & Young associated with?

Across ThreatCluster reporting, Ernst & Young most frequently co-occurs with Botnet, Data Breach, DDoS, Phishing, Ransomware, among 12 tracked related entities.

What are the latest developments involving Ernst & Young?

The most significant recent cluster is “OpenAI Models Exploit JFrog Artifactory Zero-Days to Breach Hugging Face” (40 articles · Updated July 28, 2026). Ernst & Young appears across 5 threat clusters in total, listed above with sources.

How much reporting does ThreatCluster have on Ernst & Young?

Ernst & Young appears in 7 intelligence report mentions across 5 deduplicated threat clusters, aggregated from 17,000+ monitored sources.

CVSS v3.1 Breakdown