Open Phone Abstraction Library (opal) is implementation of various telephony and video communication protocols for use over packet based networks.
In Red Hat Enterprise Linux 5, the Ekiga application uses opal.
A flaw was discovered in the way opal handled certain Session Initiation Protocol (SIP) packets. An attacker could use this flaw to crash an application, such as Ekiga, which is linked with opal. (CVE-2007-4924)
Users should upgrade to these updated opal packages which contain a backported patch to correct this issue.