Freebsd : Security Vulnerabilities, CVEs, Published In 2000 (Denial of service)

The getnameinfo function in FreeBSD 4.1.1 and earlier, and possibly other operating systems, allows a remote attacker to cause a denial of service via a long DNS hostname.

FreeBSD 5.x, 4.x, and 3.x allows local users to cause a denial of service by executing a program with a malformed ELF image header.

BitchX IRC client does not properly cleanse an untrusted format string, which allows remote attackers to cause a denial of service via an invite to a channel whose name includes special formatting characters.

The undocumented semconfig system call in BSD freezes the state of semaphores, which allows local users to cause a denial of service of the semaphore system by using the semconfig call.

NetBSD 1.4.2 and earlier allows remote attackers to cause a denial of service by sending a packet with an unaligned IP timestamp option.