Nearly half a million members of Patelco Credit Union, with branches throughout the Bay Area and Northern California, lost access to banking services after a ransomware attack over the weekend.
The Dublin-based credit union announced on social media at 7am on Saturday that its services, including online banking, mobile app, direct deposit, transfers and debit and credit card transactions, were unavailable.
Patelco members received an email from President and CEO Erin Mendez on Sunday afternoon about a “serious security incident,” although details about the incident were not initially disclosed.
The email said the credit union was working with cybersecurity experts to assess the situation and restore services. Mendez also said an estimated restoration time was not available.
In an email Monday, a Patelco spokesperson clarified that the security incident was a ransomware attack that required it to “proactively shut down some of our day-to-day banking systems in order to contain and correct the issue.”
Ransomware is a type of malicious software that prevents access to a computer system or network, accompanied by a demand for payment to regain access. Victims who pay the ransom have no guarantee that encrypted files will be unlocked, and attacks often result in costly disruptions to operations and loss of critical data.
A ransomware attack against the City of Oakland’s computer network last year resulted in the release of personal information of thousands of current and former employees on the so-called dark web.
The email said Patelco members could still use ATMs and that its branches and call center were open and operating regular business hours, albeit with longer wait times. Patelco also said its employees will not be able to access individual account details during the outage.
“We have engaged a leading third-party cyber security forensics firm to help us investigate and recover as quickly as possible,” the Patelco spokesperson said. “Please know that our team and third-party partners are working around the clock to get back up and running. We are committed to providing transparent and frequent updates to the best of our ability, as well as the best possible service that we can, given We sincerely apologize for the inconvenience this cyber attack has caused our members.
As of 3:30 p.m., electronic transactions such as transfers, direct deposits, balance inquiries and online bank bill payments were unavailable, including the Zelle digital payment system. The debit and credit card transaction were “operating in a limited capacity,” the credit union said. Furthermore, both the website and the mobile app were still not working.
Cash withdrawals and deposits were available at Patelco ATMs and at 30,000 shared branch ATMs in the U.S., Patelco said.
The credit union said further communications regarding the ransomware attack incident, including updates on system functionality, will be posted at: patelco.org/securityupdate. As of 5:00 p.m. Monday, the website was down.
The US Cyber Threat Integration Center says the number of claims of ransomware attacks worldwide in 2023 increased 74% compared to 2022. Meanwhile, ransomware affected 66% of organizations in 2023, according to a recent report.
Patelco is the nation’s 27th largest credit union with $9.8 billion in assets and 455,000 members with more than 1 million accounts, according to data from the Federal Reserve. The nonprofit credit union has 37 branches in the Bay Area and Sacramento area. It is one of the oldest credit unions in the US, founded in 1936 for employees of the former Pacific Telephone and Telegraph Company, now known as AT&T.