Flightradar24, the global flight-tracking website, has been hacked and user passwords potentially exposed.
While the organisation claims that the compromised passwords were hashed, it may not take a determined attacker long to crack them.
Stockholm-based Flightradar24 informed users via email earlier this week, and in a subsequent forum post confirmed that the emails were genuine.
The website shows aviation enthusiasts in real-time aircraft movements and other flight information.
"The security breach may have compromised the email addresses and hashed passwords for a small subset of Flightradar24 users (those who registered prior to March 16, 2016)," an adminstrator said.
"We would like to apologize that this breach occurred and for the inconvenience this may cause. We would also like to stress that we have no indication any of personal information was compromised.
"Please note that no payment information has been compromised. Flightradar24 neither handles nor stores payment information."
The company goes on to explain that the breach, first reported by ITNews, was limited to one server, which was "promptly" shut down once the intrusion had been discovered.
The company is advising that users change the password for their Flightradar24, and that they change it on other services that may share re-use same login credentials.
"Please accept our sincere apologies for any inconveniences caused," the firm continues.
"Our team will continue our thorough internal security review of our system and processes to see what more we can do to ensure that this never happens again."
New light-guiding nanoscale device can control and monitor a nanoparticle trapped in a laser beam with high sensitivity
Optical traps are scientific instruments in which a focused laser beam is used to exert an attractive or repulsive force on a microscopic object to hold it in place
Scientists estimate that the exoplanet has already lost up to 35 per cent of its mass over its lifetime
The observations were made using the Atacama Array in the Chilean desert
J1043+2408 was observed for more than 10 years, and its radio light curve exhibited a periodic signal repeating in about 563 days