Specifications

1276
Cross-Platform Release Notes for Cisco IOS Release 12.0S
OL-1617-14 Rev. Q0
Resolved Caveats—Cisco IOS Release 12.0(27)S4
• CSCee35125
Symptoms: A Cisco router may crash when you enter the clear ip route * command.
Conditions: This symptom is observed when the routing table has a default route.
Workaround: There is no workaround.
• CSCee67450
A Cisco device running Cisco IOS and enabled for the Border Gateway Protocol (BGP) is
vulnerable to a Denial of Service (DoS) attack from a malformed BGP packet. Only devices with
the bgp log-neighbor-changes command configured are vulnerable. The BGP protocol is not
enabled by default, and must be configured in order to accept traffic from an explicitly defined peer.
Unless the malicious traffic appears to be sourced from a configured, trusted peer, it would be
difficult to inject a malformed packet.
If a misformed packet is received and queued up on the interface, this bug may also be triggered by
other means which are not considered remotely exploitable such as the use of the show ip bgp
neighbors command or running the debug ip bgp neighbor updates command for a configured
BGP neighbor.
Cisco has made free software available to address this problem.
For more details, please refer to this advisory, available at
http://www.cisco.com/warp/public/707/cisco-sa-20050126-bgp.shtml
• CSCee85676
Symptoms: When VPNv4 route advertisement are received after BGP has converged, the existing
path is updated but imported paths from the original path are not updated accordingly.
Conditions: This symptom is observed on a Cisco router that functions as a PE router when the
maximum-paths number-of-paths import number-of-paths command is enabled. The symptom
occurs when the path attributes are changed dynamically instead of the path being completely
withdrawn and readvertised.
Workaround: Withdraw the prefix from the remote PE router and then readvertise the prefix.
• CSCee86530
Symptoms: A BGP update that is sent to a connected P router fails to report the martian next-hop
log message when the next-hop field in the attribute of the BGP update is set to 255.255.255.255
(that is, all 1ís). The P router does deny the advertisement of the MP_REACH_NLRI attribute to the
other PE routers, but there is no log message to indicate that it is denying the advertisement and why
it does so.
Conditions: This symptom is observed during MP-BGP negative testing for the MP_REACH
attribute.
Workaround: There is no workaround.
• CSCef91275
Symptoms: An MPLS TE tunnel stays stuck in the “Path Half Admitting” state, as is shown by the
output of the show mpls traffic-eng tunnel command, thereby preventing the tunnel from coming
up.
Conditions: This symptom may be observed when a particular third-party router that functions as
the headend for the MPLS TE tunnel sends a Path message to a Cisco router that functions as the
midpoint for the router MPLS TE tunnel and that does not have the mpls traffic-eng tunnels
interface configuration command enabled on the outbound interface that would be used to forward
the Path message.