While analyzing root cause analysis of a vulnerability using windbg we use to put a command kb to view the stack trace. But after viewing the stack trace how to analyze or confirm the presence of vulnerability.Below is the some few listing after kb command

0:000> k
ChildEBP RetAddr  
**0012fb88 008bee28 libwireshark!snmp_usm_password_to_key_sha1**
0012fba8 008c07af libwireshark!set_ue_keys+0x58
0012fbc0 008c060a libwireshark!ue_se_dup+0x10f
0012fbdc 006e017a libwireshark!renew_ue_cache+0x5a
0012fbe8 006d19a3 libwireshark!uat_load+0x18a
0012fc04 0069faad libwireshark!uat_load_all+0x53
0012fc44 0069ff59 libwireshark!init_prefs+0x6d
0012fc58 00420673 libwireshark!read_prefs+0x19
0012fcb4 0041e5c8 wireshark!read_configuration_files+0x23
0012ff18 00420a81 wireshark!main+0x6b8
0012ff30 00521bae wireshark!WinMain+0x61
0012ffc0 7c817067 wireshark!__tmainCRTStartup+0x140
0012fff0 00000000 kernel32!BaseProcessStart+0x23

if we see the first line by stack trace which is the actual crash 0012fb88 008bee28 libwireshark!snmp_usm_password_to_key_sha1 but how to determine which type of bug is?

If you see above we saw the stack trace.so how to reach the actual point where vulnerability is triggered, like from where to start looking for vulnerability?