Signal handler race condition in OpenSSH before 4.4 allows remote attackers to cause a denial of service (crash), and possibly execute arbitrary code if GSSAPI authentication is enabled, via unspecified vectors that lead to a double-free.
Unspecified vulnerability in portable OpenSSH before 4.4, when running on some platforms, allows remote attackers to determine the validity of usernames via unknown vectors involving a GSSAPI "authentication abort."
sshd in OpenSSH before 4.4, when using the version 1 SSH protocol, allows remote attackers to cause a denial of service (CPU consumption) via an SSH packet that contains duplicate blocks, which is not properly handled by the CRC compensation attack detector.
OpenSSH on FreeBSD 5.3 and 5.4, when used with OpenPAM, does not properly handle when a forked child process terminates during PAM authentication, which allows remote attackers to cause a denial of service (client connection refusal) by connecting multiple times to the SSH server, waiting for the password prompt, then disconnecting.
scp in OpenSSH 4.2p1 allows attackers to execute arbitrary commands via filenames that contain shell metacharacters or spaces, which are expanded twice.
sshd in OpenSSH before 4.2, when GSSAPIDelegateCredentials is enabled, allows GSSAPI credentials to be delegated to clients who log in using non-GSSAPI methods, which could cause those credentials to be exposed to untrusted users or hosts.
SSH, as implemented in OpenSSH before 4.0 and possibly other implementations, stores hostnames, IP addresses, and keys in plaintext in the known_hosts file, which makes it easier for an attacker that has compromised an SSH user's account to generate a list of additional targets that are more likely to have the same password or key.
The default configuration for OpenSSH enables AllowTcpForwarding, which could allow remote authenticated users to perform a port bounce, when configured with an anonymous access program such as AnonCVS.