The failure was discovered because of a malfunction in the BGP implementation of another vendor. There is no workaround. The vulnerability can be exercised repeatedly, affecting core routers, creating widespread network outages. This vulnerability can only be exercised in configurations that include both BGP and inbound route filtering on affected software. The following table summarizes the Cisco IOS software releases that are known to be affected, and the earliest estimated dates of availability for the recommended fixed versions.
Dates are always tentative and subject to change.
Each row of the table describes a release train and the platforms or products for which it is intended. Rebuild Constructed from the previous maintenance or major release in the same train, it contains the fix for a specific defect. Although it receives less testing, it contains only the minimal changes necessary to effect the repair. Interim Built at regular intervals between maintenance releases and receive less testing. Interims should be selected only if there is no other suitable release that addresses the vulnerability, and interim images should be upgraded to the next available maintenance release as soon as possible.