Okta has shed more than $2 billion from its market valuation since the company disclosed a hack of its support systems on Friday. The high-profile incident is the latest in a string of incidents that have been tied to Okta or its products, including a spate of intrusions at casinos that crippled Las Vegas hotel rooms for days.

Okta shares slumped more than 11% on Friday after the company said that an unidentified hacking group was able to access client files through a support system. The company did not provide more details beyond a set of technical identifiers.

The company’s stock continued to fall in Monday trading, ultimately closing down 8.1%.

Okta is a lesser-known name but forms a critical part of cybersecurity systems at major corporations. The identity-management company boasts more than 18,000 customers who use its products to provide a single login point for many different platforms that a given company uses. Zoom, for example, uses Okta to give “seamless” access through a single login to the company’s Google Workspace, ServiceNow, VMWare and Workday platforms.

Okta said it had communicated with all affected clients in Friday’s announcement. At least one of those clients said it had alerted Okta about a potential breach weeks earlier.

In a separate post Friday, privately held identity management firm BeyondTrust, said that it had told Okta’s security teams about suspicious activity in BeyondTrust’s own Okta systems on October 2. Okta didn’t initially acknowledge the incident as a breach after BeyondTrust alerted the company, despite what BeyondTrust described as concerns that “there was a high likelihood of compromise within Okta support and that we were likely not the only customer impacted.”