UBUNTU-CVE-2015-5600

The kbdintnextdevice function in auth2-chall.c in sshd in OpenSSH through 6.9 does not properly restrict the processing of keyboard-interactive devices within a single connection, which makes it easier for remote attackers to conduct brute-force attacks or cause a denial of service (CPU consumption) via a long and duplicative list in the ssh -oKbdInteractiveDevices option, as demonstrated by a modified client that provides a different password for each pam element on this list.

References

Affected packages

Ubuntu:14.04:LTS / openssh

Package

Name: openssh
Purl: pkg:deb/ubuntu/openssh@1:6.6p1-2ubuntu2.2?arch=source&distro=trusty

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

1:6.6p1-2ubuntu2.2

Affected versions

1:6.*

1:6.2p2-6

1:6.2p2-6ubuntu1

1:6.4p1-1

1:6.4p1-2

1:6.5p1-1

1:6.5p1-2

1:6.5p1-3

1:6.5p1-4

1:6.5p1-6

1:6.6p1-1

1:6.6p1-2

1:6.6p1-2ubuntu1

1:6.6p1-2ubuntu2

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "openssh-client"
        },
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "openssh-server"
        },
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "openssh-sftp-server"
        },
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "ssh"
        },
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "ssh-askpass-gnome"
        },
        {
            "binary_version": "1:6.6p1-2ubuntu2.2",
            "binary_name": "ssh-krb5"
        }
    ]
}