Cisco Cisco IOS Software Release 12.2

Conditions: This symptom is observed after ACLs have been updated dynamically or after the router 
has responded dynamically to an IDS signature.

Workaround: Disable IP Inspect and IDS. 

CSCee49862

Symptoms: A Cisco 7500 series multichannel T3 port adapter (PA-MC-2T3+) may not provide a 
two-second delay before bringing down the T3 controller.

Conditions: This symptom is observed when an alarm as defined in the ANSI T1.231 specification 
occurs.

Workaround: There is no workaround. 

CSCin66542

Symptoms: The line protocol on a T1 of a T3 controller in a PA-MC-2T3+ port adapter may stay in 
the down state even when looped.

Conditions: This symptom is observed on a Cisco 7200 series and Cisco 7500 series.

Workaround: There is no workaround. 

Cisco IOS Release 12.2(19b) is a rebuild release for Cisco IOS Release 12.2(19). The caveats in this 
section are resolved in Cisco IOS Release 12.2(19b) but may be open in previous Cisco IOS releases.

The following information is provided for each caveat:

Symptoms: A description of what is observed when the caveat occurs. 

Conditions: The conditions under which the caveat has been known to occur. 

Workaround: Solutions, if available, to counteract the caveat. 

CSCdx76632

Symptoms:   A Cisco AS5300 that is functioning as a voice gateway may reload because of an 
incoming bus error exception.

Conditions:   This symptom is observed on a Cisco AS5300 that is running Cisco IOS 
Release 12.2(6d).

Workaround:   There is no workaround. 

CSCdx77253

Cisco products running IOS contain vulnerabilities in the processing of H.323 messages, which are 
typically used in packetized voice or multimedia applications. Features such as NAT and IOS 
Firewall must inspect H.323 messages and may be vulnerable as well. A test suite has been 
developed by the University of Oulu to target this protocol and identify vulnerabilities. 

Support for the H.323 protocol was introduced in Cisco IOS Software Release 11.3T, and all later 
Cisco IOS releases are affected if configured for various types of Voice/Multimedia Application 
support. The vulnerabilities can be exploited repeatedly to produce a denial of service (DoS).

There are workarounds available that may mitigate the impact, but these techniques may not be 
appropriate for use in all customer networks.