Apple said Wednesday it will stop supporting the encryption standard Secure Sockets Layer 3.0 for its push notifications service in response to a vulnerability identified earlier this month in the aging protocol.
Apple announced on its developer site that it will switch on October 29 from SSL 3.0 to Transport Layer Security (TLS), SSL's more modern, less vulnerable younger sibling. , the vulnerability -- called Poodle -- allows encrypted information to be exposed by an attacker with network access.
"Providers using only SSL 3.0 will need to support TLS as soon as possible to ensure the Apple Push Notification service continues to perform as expected," Apple said in its bulletin. "Providers that support both TLS and SSL 3.0 will not be affected and require no changes."
To help developers test compatibility, Apple said it has already disabled SSL 3.0 in the development environment on its Provider Communication interface.
Poodle, which stands for Padding Oracle On Downgraded Legacy Encryption (PDF), is a problem because it's used by both websites and Web browsers. Both must be reconfigured to prevent using SSL 3.0, and Poodle will remain a problem as long as SSL 3.0 is supported.
Once the most advanced form of Web encryption in use, the 15-year-old SSL 3.0 is used by few websites anymore, according to a study by the University of Michigan. However, Poodle still poses a threat because attackers can force browsers to downgrade to SSL 3.0.
Twitter already notified its users that it has disabled SSL 3.0 support, while Mozilla advised Firefox users to install a Mozilla security add-on that disables SSL 3.0. Along with Google and Mozilla, the University of Michigan researchers detailed how to disable SSL 3.0 for Internet Explorer.
Mozilla plans to disable SSL 3.0 in Firefox 34, the next version of the open-source browser. It's currently in beta testing, with a release planned for the end of November. Mozilla has been testing the change in its Aurora version of Firefox, the precursor to the beta version, and so far, "There has been much less screaming about this than I anticipated," said Mozilla's Martin Thomson on Wednesday, discussing the change on Mozilla's bug-tracker. Complaints would come from people who couldn't use Web sites that required SSL 3.0.
CNET News staff writer Stephen Shankland contributed to this report.