The exact error message can read: 

Mar 2 02:26:09.923: %SYS-2-MALLOCFAIL: Memory allocation of 4676 bytes failed from 0xC7C98, alignment 4 Pool: I/O Free: 4704 Cause: Memory fragmentation Alternate Pool: None Free: 0 Cause: No Alternate pool .

This problem is tracked in Cisco bug ID CSCsd77228. It is first found in Cisco IOS® Software Release 12.3(8)JA. A Cisco Aironet access point (AP) or bridge can generate large amounts of multicast traffic when it receives certain types of Internet Group Management Protocol (IGMP) queries when the IGMP snooping feature is enabled on the AP, which is the default.

The problem exists in Cisco IOS Software Release 12.3(8)JA, specifically for these APs and bridges:

• AP 1240
  
  
• AP 1130
  
  
• BR 1310

Disable the IGMP snooping feature on the AP or bridge in order to workaround this problem:

ap(config)#no ip igmp snooping

The problem is fixed in these Cisco IOS software releases:

• Cisco IOS Software Release 12.3(11)JA
  
  
• Cisco IOS Software Release 12.3(8)JA02
  
  
• Cisco IOS Software Release 12.3(8)JEA

Upgrade the APs to one of these versions in order to resolve the problem.