Flaw bug created to hold information about an old flaw we knew something about. For more details see the MITRE CVE description.
MITRE description: Heap-based buffer overflow in Mozilla Thunderbird before 1.5.0.5 and SeaMonkey before 1.0.3 allows remote attackers to cause a denial of service (crash) via a VCard attachment with a malformed base64 field, which copies more data than expected due to an integer underflow.