Cisco Cisco IOS Software Release 12.0 S Release Notes
1504
Cross-Platform Release Notes for Cisco IOS Release 12.0S
OL-1617-14 Rev. Q0
Resolved Caveats—Cisco IOS Release 12.0(26)S1
•
CSCeb69295
Symptoms: A redistributed static route may not be advertised to any Border Gateway Protocol
(BGP) peer, even though the route is selected as the best path in the BGP table.
(BGP) peer, even though the route is selected as the best path in the BGP table.
Conditions: This symptom is observed when the MPLS VPN Carrier Supporting Carrier IPv4 BGP
Label Distribution feature is enabled and when the IP version 4 (IPv4) address family is missing
from the running configuration.
Label Distribution feature is enabled and when the IP version 4 (IPv4) address family is missing
from the running configuration.
Workaround: There is no workaround.
•
CSCec16481
A Cisco device running Internetwork Operating System (IOS) and enabled for the Open Shortest
Path First (OSPF) Protocol is vulnerable to a Denial of Service (DoS) attack from a malformed
OSPF packet. The OSPF protocol is not enabled by default.
Path First (OSPF) Protocol is vulnerable to a Denial of Service (DoS) attack from a malformed
OSPF packet. The OSPF protocol is not enabled by default.
The vulnerability is only present in IOS release trains based on 12.0S, 12.2, and 12.3. Releases based
on 12.0, 12.1 mainlines and all IOS images prior to 12.0 are not affected. Refer to the Security
Advisory for a complete list of affected release trains.
on 12.0, 12.1 mainlines and all IOS images prior to 12.0 are not affected. Refer to the Security
Advisory for a complete list of affected release trains.
Further details and the workarounds to mitigate the effects are explained in the Security Advisory
which is available at the following URL:
which is available at the following URL:
.
•
CSCec78690
Symptoms: In rare situations, a User Datagram Protocol (UPD) Gigabit Route Processor (GRP)
leader may bounce and cause problems when trying to converge other Border Gateway Protocol
(BGP) peers.
leader may bounce and cause problems when trying to converge other Border Gateway Protocol
(BGP) peers.
Conditions: This symptom occurs rarely on a Cisco GRP.
Workaround: Enter the clear ip bgp * EXEC command to clear the symptom.
•
CSCeb85136
Symptoms: An IP packet that is sent with an invalid IP checksum may not be dropped.
Conditions: This symptom is observed if the IP checksum is calculated with a decreased time-to-live
(TTL) value. For example, in the situation where the IP checksum must be 0x1134 with a TTL of 3,
if the packet is sent with an IP checksum of 0x1234 that is calculated by using a TTL value of 2, the
packet is not dropped. In all other cases, packets with incorrect checksums are dropped.
(TTL) value. For example, in the situation where the IP checksum must be 0x1134 with a TTL of 3,
if the packet is sent with an IP checksum of 0x1234 that is calculated by using a TTL value of 2, the
packet is not dropped. In all other cases, packets with incorrect checksums are dropped.
Workaround: There is no workaround.
•
CSCec06466
Symptoms: A Cisco router may reload unexpectedly when the Designated Forwarder (DF) interface
is changed to an interface that is already in the Outgoing Interface list (O-list).
is changed to an interface that is already in the Outgoing Interface list (O-list).
Conditions: This symptom is observed on a Cisco router that is configured for multicast
Bidirectional PIM (Bidir-PIM).
Bidirectional PIM (Bidir-PIM).
Workaround: There is no workaround.
•
CSCec10494
Symptoms: A Cisco router or switch may reload unexpectedly when you enter the show ip igmp
tracking detail EXEC command.
tracking detail EXEC command.
Conditions: This symptom is observed when the ip igmp explicit-tracking interface configuration
command is enabled and the entries in the cache have expired.
command is enabled and the entries in the cache have expired.
Workaround: There is no workaround.