Ubuntu Security Notice 512-1 – It was discovered that Quagga did not correctly verify OPEN messages or COMMUNITY attributes sent from configured peers. Malicious authenticated remote peers could send a specially crafted message which would cause bgpd to abort, leading to a denial of service.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/59371/USN-512-1.txt
Source: https://packetstormsecurity.com/files/59371/Ubuntu-Security-Notice-512-1.html