Goldman Sachs and Man Group exposed in EY data breach

According to GBHackers, the incident involved a platform supporting EY's tax services, not the financial firms' own networks[1]. Bloomberg separately reported that Goldman Sachs Group Inc.'s data was exposed earlier this year in a hack of accounting firm EY, according to a person familiar with the matter.[2]Cybersecurity News reports that letters sent at the end of September said an unauthorized third party accessed the platform between March 28 and April 12, 2026, and downloaded documents connected to multiple EY clients.[3] The outlet says the data included names, addresses, tax identification numbers, email addresses, and financial details.[3]Cybersecurity News also reports that EY detected unusual activity on April 23, eleven days after the last reported unauthorized access.[3]GBHackers reports that Goldman said its systems were unaffected and client assets remained safe.[1] The same outlet says the bank's Technology Risk team was reviewing that work and requiring evidence and outside validation of EY's fixes.[1]According to GBHackers, Man Group likewise said its systems were not compromised[1]. The outlet adds that Tishman Speyer also received notice that information linked to its investors might have been affected.[1]Traders Union reports that EY attributed the incident to a Checkmarx software vulnerability, reported the breach to regulators across four U.S. states, and is offering affected individuals credit monitoring.[4]GBHackers says ShinyHunters claimed responsibility in July through its dark web leak site[1]. The outlet notes that those statements remain attacker claims and should not be treated as independently confirmed findings[1].