CVE 2006-2223
RIPd in Quagga 0.98 and 0.99 before 20060503 does not properly implement configurations that (1) disable RIPv1 or (2) require plaintext or MD5 authentication, which allows remote attackers to obtain sensitive information (routing state) via REQUEST packets such as SEND UPDATE.
See the 
CVE page on Mitre.org
for more details.
