ONE of Ireland's most-used daily messaging services has been hacked, with phone numbers and usernames published.
Snapchat, which is used by 255,000 Irish adults to send pictures and messages on a daily basis, had 4.6 million of its users' details published on the internet by anonymous hackers.
It has been linked to an organisation dedicated to highlighting flaws in the social media service's security settings.
The published phone numbers do not include the last two digits, however.
The information was offered for download on a website called SnapchatDB.info, which claimed it had acquired the information "through the recently patched Snapchat exploit".
This was a technical reference to the fact that personal data held by Snapchat could apparently be accessed by hackers through security vulnerabilities.
A statement on the website, which has since been taken offline, said: "The company was too reluctant at patching the exploit until they knew it was too late, and companies that we trust with our information should be more careful when dealing with it.
"For now, we have censored the last two digits of the phone numbers in order to minimise spam and abuse."
On Christmas Eve, an Australian hacking group known as GibsonSec published an exploit, which alleged to a possible attack where one could compile a list of user details.
The group claimed that Snapchat had made little effort to fix vulnerabilities it had earlier warned about in August.
GibsonSec claimed on Twitter that it was not responsible for yesterday's hacking, but that "it was a matter of time 'til something like that happened".
IT law expert TJ McIntyre told the Irish Independent it was "particularly reprehensible" if Snapchat failed to plug its security hole.
"It appears that they didn't respond to the warnings that were given. That's particularly reprehensible. There is a lot of information here about a lot of children. There is information here that could compromise people's information on other services also."
Days before the hacking, Snapchat reassured its estimated 30 million active users that over the past year it had now implemented safeguards, which would make an attack more difficult.
"We recently added additional counter-measures and continue to make improvements to combat spam and abuse," said the US-based company.
Snapchat is a photo messaging app that allows users to share images -- but they fade away after a matter of seconds and are deleted from the Snapchat servers.
According to the Irish polling firm Ipsos MRBI, 13pc of Irish adults use Snapchat.
GibsonSec stated on Twitter that only users located in the United States and Canada had been affected by the attack.