SSH Communications Security's Secure Shell Server: SFTP privilege escalation

Background

The SSH Secure Shell Server from SSH Communications Security (www.ssh.com) is a commercial SSH implementation available free for non-commercial use.

Description

The SSH Secure Shell Server contains a format string vulnerability in the SFTP code that handles file transfers (scp2 and sftp2). In some situations, this code passes the accessed filename to the system log. During this operation, an unspecified error could allow uncontrolled stack access.

Impact

An authenticated system user may be able to exploit this vulnerability to bypass command restrictions, or run commands as another user.

Workaround

There is no known workaround at this time.

Resolution

This package is currently masked, there is no upgrade path for the 3.2.x version, and a license must be purchased in order to update to a non-vulnerable version. Because of this, we recommend unmerging this package:

 # emerge --ask --verbose --unmerge net-misc/ssh