ICANN has revealed that it took down its top-level domain application system yesterday after discovering a potentially serious data leakage vulnerability.
As El Reg reported earlier today, ICANN shut down its TLD Application System (TAS) – the web application companies use to apply for new gTLDs – due to unspecified "unusual behaviour".
The organisation has now revealed that while there was no "attack" as such, it had found that some TAS users could access data belonging to other TAS users.
"We have learned of a possible glitch in the TLD application system software that has allowed a limited number of users to view some other users’ file names and user names in certain scenarios," COO Akram Atallah said in a statement.
"Out of an abundance of caution, we took the system offline to protect applicant data," he added. "We are examining how this issue occurred and considering appropriate steps forward."
The vulnerability has potentially serious implications due to the level of secrecy surrounding the majority of new gTLD applications.
Companies in general don't want to reveal which gTLDs they are applying for while the ICANN application window is still open. If it were revealed that Coca-Cola had applied for .drink, for example, that might prompt Pepsi to file a competing application.
Because ICANN's method of last resort for resolving these so-called "contention sets" is an auction, a prematurely revealed application could therefore wind up costing hundreds of thousands of dollars – even millions of dollars – more.
It's quite possible that gTLD strings may have been included in the leaked user names and file names, though ICANN has yet to confirm the extent of this problem.
It's also not yet known which applicants had access to which other applicants' data, and whether any of the leaked information was acted upon.
The new gTLD application window was due to close yesterday at 1159 UTC, but ICANN shut down the TAS about 12 hours before the deadline after becoming aware of the vulnerability.
The filing deadline has now been extended until next Friday, but ICANN does not plan to bring the TAS back online until Tuesday, by which time it expects to have fixed the bug. ®