Movie ticket subscription service MoviePass has exposed tens of thousands of customer card numbers and personal credit cards because a critical server was not protected with a password.

Mossab Hussein, a security researcher at Dubai-based cybersecurity firm SpiderSilk, found an exposed database on one of the company’s many subdomains. The database was massive, containing 161 million records at the time of writing and growing in real time. Many of the records were normal computer-generated logging messages used to ensure the running of the service — but many also included sensitive user information, such as MoviePass customer card numbers.

These MoviePass customer cards are like normal debit cards: they’re issued by Mastercard and store a cash balance, which users who sign up to the subscription service can use to pay to watch a catalog of movies. For a monthly subscription fee, MoviePass uses the debit card to load the full cost of the movie, which the customer then uses to pay for the movie at the cinema.

We reviewed a sample of 1,000 records and removed the duplicates. A little over half contained unique MoviePass debit card numbers. Each customer card record had the MoviePass debit card number and its expiry date, the card’s balance and when it was activated.

The database had more than 58,000 records containing card data — and was growing by the minute.

We also found records containing customers’ personal credit card numbers and their expiry date — which included billing information, including names and postal addresses. Among the records we reviewed, we found records with enough information to make fraudulent card purchases.

Some records, however, contained card numbers that had been masked except for the last four digits.

The database also contained email address and some password data related to failed login attempts. We found hundreds of records containing users’ email addresses and presumably incorrectly typed passwords — which was logged — in the database. We verified this by attempting to log into the app with an email address and password that didn’t exist but only we knew. Our dummy email address and password appeared in the database almost immediately.

None of the records in the database were encrypted.

Hussain contacted MoviePass chief executive Mitch Lowe by email — which TechCrunch has seen — over the weekend but did not hear back. It was only after TechCrunch reached out Tuesday when MoviePass took the database offline.

The database was exposed for months. Yonathan Klijnsma, threat researcher at cyberthreat intelligence firm RiskIQ, found evidence that the database was open from early May. Then, after we published this story, security researcher Nitish Shah told TechCrunch he also found the exposed database months earlier. “I even notified them, but they [didn’t bother] to reply or fix it,” he said. He provided a screenshot of the exposed database for proof, which we verified.

We asked MoviePass several questions — including why the initial email disclosing the security lapse was ignored, for how long the server was exposed and its plans to disclose the incident to customers and state regulators.

Almost a day after we published, MoviePass acknowledged the security incident in a boilerplate statement but did not answer our questions.

“MoviePass recently discovered a security vulnerability that may have exposed customer records. After discovering the vulnerability, we immediately secured our systems to prevent further exposure and to mitigate the potential impact of this incident,” said Lowe. “MoviePass takes this incident seriously and is dedicated to protecting our customers’ information. We are working diligently to investigate the scope of this incident and its potential impact on our customers. Once we gain a full understanding of the incident, we will promptly notify any affected subscribers and the appropriate regulators or law enforcement.”

MoviePass has been on a roller coaster since it hit mainstream audiences last year. The company quickly grew its customer base from 1.5 million to 2 million customers in less than a month. But MoviePass took a tumble after critics said it grew too fast, forcing the company to cease operating briefly after the company ran out of money. The company later said it was profitable, but then suspended service, supposedly to work on its mobile app. It now says it has “restored [service] to a substantial number of our current subscribers.”

Leaked internal data from April said its customer numbers went from three million subscribers to about 225,000. And just this month MoviePass reportedly changed user passwords to hobble access for customers who use the service extensively.

Hussein said the company was negligent in leaving data unencrypted in an exposed, accessible database.

“We keep on seeing companies of all sizes using dangerous methods to maintain and process private user data,” Hussein told TechCrunch. “In the case of MoviePass, we are questioning the reason why would internal technical teams ever be allowed to see such critical data in plaintext — let alone the fact that the data set was exposed for public access by anyone,” he said.

The security researcher said he found the exposed database using his company-built web mapping tools, which peeks into non-password protected databases that are connected to the internet, and identifies the owner. The information is privately disclosed to companies, often in exchange for a bug bounty.

Hussein has a history of finding exposed databases. In recent months he found one of Samsung’s development labs exposed on the internet. He also found an exposed backend database belonging to Blind, an anonymity-driven workplace social network, exposing private user data.

Updated with additional information about a second security researcher. Also updated with new data from RiskIQ that shows the database was exposed as early as May, and not June as we had earlier reported, and a statement from MoviePass.

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