OpenSSH < 4.7 Trusted X11 Cookie Connection Policy Bypass

high Nessus Plugin ID 44078
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Synopsis

Remote attackers may be able to bypass authentication.

Description

According to the banner, OpenSSH earlier than 4.7 is running on the remote host. Such versions contain an authentication bypass vulnerability. In the event that OpenSSH cannot create an untrusted cookie for X, for example due to the temporary partition being full, it will use a trusted cookie instead. This allows attackers to violate intended policy and gain privileges by causing their X client to be treated as trusted.

Solution

Upgrade to OpenSSH 4.7 or later.

See Also

http://www.openssh.com/txt/release-4.7

Plugin Details

Severity: High

ID: 44078

File Name: openssh_47.nasl

Version: 1.9

Type: remote

Family: Misc.

Published: 10/4/2011

Updated: 7/16/2018

Dependencies: ssh_detect.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.3

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:openbsd:openssh

Exploit Ease: No known exploits are available

Patch Publication Date: 9/5/2007

Vulnerability Publication Date: 9/5/2007

Reference Information

CVE: CVE-2007-4752, CVE-2007-2243

BID: 25628

CWE: 20, 287