CVE-2016-0778

The (1) roaming_read and (2) roaming_write functions in roaming_common.c in the client in OpenSSH 5.x, 6.x, and 7.x before 7.1p2, when certain proxy and forward options are enabled, do not properly maintain connection file descriptors, which allows remote servers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact by requesting many forwardings.

An information leak flaw was found in the way the OpenSSH client roaming feature was implemented. A malicious server could potentially use this flaw to leak portions of memory (possibly including private SSH keys) of a successfully authenticated OpenSSH client (CVE-2016-0777).

A buffer overflow flaw was found in the way the OpenSSH client roaming feature was implemented. A malicious server could potentially use this flaw to execute arbitrary code on a successfully authenticated OpenSSH client if that client used certain non-default configuration options (CVE-2016-0778).

The issue only affects OpenSSH clients making use of the ProxyCommand feature. This update disables the roaming feature completely.

These are all security issues fixed in the openssh-7.2p2-3.1 package on the GA media of openSUSE Tumbleweed.

This update for openssh-openssl1 fixes the following issues:

• CVE-2016-0777: A malicious or compromised server could cause the OpenSSH client to expose part or all of the client's private key through the roaming feature (bsc#961642)
• CVE-2016-0778: A malicious or compromised server could could trigger a buffer overflow in the OpenSSH client through the roaming feature (bsc#961645)

This update disables the undocumented feature supported by the OpenSSH client and a commercial SSH server.

This update for openssh fixes the following issues:

• CVE-2016-0777: A malicious or compromised server could cause the OpenSSH client to expose part or all of the client's private key through the roaming feature (bsc#961642)
• CVE-2016-0778: A malicious or compromised server could could trigger a buffer overflow in the OpenSSH client through the roaming feature (bsc#961645)

This update disables the undocumented feature supported by the OpenSSH client and a commercial SSH server.

This update for openssh fixes the following issues:

• CVE-2016-0777: A malicious or compromised server could cause the OpenSSH client to expose part or all of the client's private key through the roaming feature (bsc#961642)
• CVE-2016-0778: A malicious or compromised server could could trigger a buffer overflow in the OpenSSH client through the roaming feature (bsc#961645)

This update disables the undocumented feature supported by the OpenSSH client and a commercial SSH server.

This update for openssh fixes the following issues:

• CVE-2016-0777: A malicious or compromised server could cause the OpenSSH client to expose part or all of the client's private key through the roaming feature (bsc#961642)
• CVE-2016-0778: A malicious or compromised server could could trigger a buffer overflow in the OpenSSH client through the roaming feature (bsc#961645)

This update disables the undocumented feature supported by the OpenSSH client and a commercial SSH server.

It was discovered that the OpenSSH client experimental support for resuming connections contained multiple security issues. A malicious server could use this issue to leak client memory to the server, including private client user keys.