Customer support company Zendesk revealed on Wednesday that it has become aware of a security incident impacting thousands of accounts activated before November 2016.
Zendesk says its customer support platform is used by 145,000 entities across 160 countries and territories, but the firm claims the 2016 data breach impacted only around 10,000 Support and Chat accounts.
The company learned about the hack recently from a third party. The investigation into the incident is ongoing, but Zendesk has so far determined that roughly 10,000 accounts, including expired trial accounts and inactive accounts, were impacted. The breach does not appear to affect accounts activated after November 1, 2016.
The attacker gained access to databases storing information on Zendesk customers and individuals who interacted with those customers via Zendesk products. The exposed information includes usernames, email addresses, phone numbers, and hashed and salted passwords. In the case of approximately 700 accounts, hackers may have also accessed TLS encryption keys and configuration settings for apps. This configuration data can include integration keys used by applications to authenticate on third-party services.
Zendesk said it found no evidence so far that any ticket data was compromised as a result of the incident. It also noted that BIME, Connect, Sell and Smooch products were not affected.
The company has decided to reset passwords for accounts that have used the same password since before November 1, 2016, if they are not using Single sign-on (SSO). The password reset procedure will also impact Guide, Talk and Explore products, which share authentication with the impacted Support product.
Zendesk has contacted law enforcement and forensics experts to assist its investigation into the incident. Customers should expect to receive more updates in the upcoming period.
Zendesk also admitted being hacked back in 2013, but at the time the company said the breach had only impacted three customers.
Zendesk shares went down 4% on Wednesday after the breach was disclosed.
Related: Internal Communications of Many Firms Exposed by Helpdesk Flaws

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.
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