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Data Breaches

Information of European Hotel Chain’s Customers Found on Unprotected Server

The personal information of many customers of European hotel chain Falkensteiner was discovered by a researcher on an unprotected server.

A researcher has discovered an unprotected server storing the personal information of a significant number of customers of European hotel chain Falkensteiner.

Austria-based Falkensteiner has hotels in Central and Eastern Europe, including in Austria, Italy, Croatia, Slovakia, Serbia and the Czech Republic.

The exposed Falkensteiner data was discovered by Anurag Sen, a researcher at cloud security firm CloudDefense.AI. Sen recently also discovered a US government server that was leaking internal US military emails

An analysis conducted by Sen showed that the exposed Falkensteiner customer data was associated with Gustaffo, a company offering IT solutions for the hospitality industry. 

The researcher says he notified both Gustaffo and Falkensteiner, but none of them responded. However, Sen noticed that the server was secured shortly after he informed the companies.

Sen told SecurityWeek that the vulnerable Elasticsearch server hosted more than 11 Gb of data before it was taken offline. He found more than 102,000 records in the exposed database, including full names, phone numbers, email addresses, and booking details. 

The researcher is unhappy with the way the issue has been handled by the impacted companies — he says they haven’t responded to his emails and haven’t notified customers about the data breach.

However, Gustaffo says they actually secured the server after learning about the leak from a different researcher. The Austria-based company, which does have a responsible disclosure program, told SecurityWeek that its assessment showed that the incident was limited to one system and the details of only approximately 13,000 individuals were exposed.

Gustaffo representatives explained that many of the records were likely duplicates as it does not store the information of more than 13,000 customers in the database. 

The company said it performed the necessary security updates to its system and it’s in touch with government authorities handling the incident. 

Falkensteiner has not responded to SecurityWeek’s repeated requests for comment.

UPDATE: Falkensteiner has provided the following statement:

“We have been informed about a possible weakness in the data base access systems at one of our subcontractors. FMTG takes the security of our customer’s data very seriously. Therefore, we are looking closely into this issue and cooperating with the subcontractor to improve their IT systems. We also informed the relevant data protection authority.”

Related: R1Soft Server Backup Manager Vulnerability Exploited to Deploy Backdoor

Related: Credential Leakage Fueling Rise in API Breaches

Related: Uber Data Leaked Following Breach at Third-Party Vendor

Written By

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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