security flaw

OpenSSH before 2.9.9, when running sftp using sftp-server and using restricted keypairs, allows remote authenticated users to bypass authorized_keys2 command= restrictions using sftp commands.

security flaw

OpenSSH 3.0.1 and earlier with UseLogin enabled does not properly cleanse critical environment variables such as LD_PRELOAD, which allows local users to gain root privileges.

libutil in OpenSSH on FreeBSD 4.4 and earlier does not drop privileges before verifying the capabilities for reading the copyright and welcome files, which allows local users to bypass the capabilities checks and read arbitrary files by specifying alternate copyright or welcome files.

Race condition in OpenBSD VFS allows local users to cause a denial of service (kernel panic) by (1) creating a pipe in one thread and causing another thread to set one of the file descriptors to NULL via a close, or (2) calling dup2 on a file descriptor in one process, then setting the descriptor to NULL via a close in another process that is created via rfork.

fts routines in FreeBSD 4.3 and earlier, NetBSD before 1.5.2, and OpenBSD 2.9 and earlier can be forced to change (chdir) into a different directory than intended when the directory above the current directory is moved, which could cause scripts to perform dangerous actions on the wrong directories.

Multiple TCP implementations could allow remote attackers to cause a denial of service (bandwidth and CPU exhaustion) by setting the maximum segment size (MSS) to a very small number and requesting large amounts of data, which generates more packets with less TCP-level data that amplify network traffic and consume more server CPU to process.

security flaw

OpenSSH before 2.9.9, while using keypairs and multiple keys of different types in the ~/.ssh/authorized_keys2 file, may not properly handle the "from" option associated with a key, which could allow remote attackers to login from unauthorized IP addresses.

The "echo simulation" traffic analysis countermeasure in OpenSSH before 2.9.9p2 sends an additional echo packet after the password and carriage return is entered, which could allow remote attackers to determine that the countermeasure is being used.

vi.recover in OpenBSD before 3.1 allows local users to remove arbitrary zero-byte files such as device nodes.

OpenSSH 2.9 and earlier does not initiate a Pluggable Authentication Module (PAM) session if commands are executed with no pty, which allows local users to bypass resource limits (rlimits) set in pam.d.

OpenSSH before 3.0.1 with Kerberos V enabled does not properly authenticate users, which could allow remote attackers to login unchallenged.

The uipc system calls (uipc_syscalls.c) in OpenBSD 2.9 and 3.0 provide user mode return instead of versus rval kernel mode values to the fdrelease function, which allows local users to cause a denial of service and trigger a null dereference.

SSH protocol 2 (aka SSH-2) public key authentication in the development snapshot of OpenSSH 2.3.1, available from 2001-01-18 through 2001-02-08, does not perform a challenge-response step to ensure that the client has the proper private key, which allows remote attackers to bypass authentication as other users by supplying a public key from that user's authorized_keys file.

security flaw

Off-by-one error in the channel code of OpenSSH 2.0 through 3.0.2 allows local users or remote malicious servers to gain privileges.

The TCP implementation in various BSD operating systems (tcp_input.c) does not properly block connections to broadcast addresses, which could allow remote attackers to bypass intended filters via packets with a unicast link layer address and an IP broadcast address.

security flaw

Integer overflow in xdr_array function in RPC servers for operating systems that use libc, glibc, or other code based on SunRPC including dietlibc, allows remote attackers to execute arbitrary code by passing a large number of arguments to xdr_array through RPC services such as rpc.cmsd and dmispd.

KAME-derived implementations of IPsec on NetBSD 1.5.2, FreeBSD 4.5, and other operating systems, does not properly consult the Security Policy Database (SPD), which could cause a Security Gateway (SG) that does not use Encapsulating Security Payload (ESP) to forward forged IPv4 packets.

PF in OpenBSD 3.0 with the return-rst rule sets the TTL to 128 in the RST packet, which allows remote attackers to determine if a port is being filtered because the TTL is different than the default TTL.

mail in OpenBSD 2.9 and 3.0 processes a tilde (~) escape character in a message even when it is not in interactive mode, which could allow local users to gain root privileges via calls to mail in cron.

Vulnerability in OpenBSD 3.0, when using YP with netgroups in the password database, causes (1) rexec or (2) rsh to run another user's shell, or (3) atrun to change to a different user's directory, possibly due to memory allocation failures or an incorrect call to auth_approval().