Accessing cross-origin objects via the Alarms API

Accessing cross-origin objects via the Alarms API

Announced

October 14, 2014

Reporter

Boris Zbarsky

Impact

High

Products

Firefox, Firefox ESR

Fixed in

• Firefox 33
• Firefox ESR 31.2

Description

Mozilla developer Boris Zbarsky reported that a malicious app could use the AlarmAPI to read the values of cross-origin references, such as an iframe's location object, as part of an alarm's JSON data. This allows a malicious app to bypass same-origin policy.

Users are only at risk for this issue if a web app has been installed.

References

• Alarms API performs unsafe toJSON conversions on content objects (CVE-2014-1583)