snmplib/mib.c in net-snmp 5.7.0 and earlier, when the -OQ option is used, allows remote attackers to cause a denial of service (snmptrapd crash) via a crafted SNMP trap message, which triggers a conversion to the variable type designated in the MIB file, as demonstrated by a NULL type in an ifMtu trap message.

Net-SNMP 5.7.1 and earlier, when AgentX is registering to handle a MIB and processing GETNEXT requests, allows remote attackers to cause a denial of service (crash or infinite loop, CPU consumption, and hang) by causing the AgentX subagent to timeout.