OpenSSH SSHFP Record Verification Weakness

medium Nessus Plugin ID 78655
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Synopsis

A secure shell client on the remote host could be used to bypass host verification methods.

Description

According to its banner, the version of OpenSSH running on the remote host is 6.1 through 6.6.

It is, therefore, affected by a host verification bypass vulnerability related to SSHFP and certificates that could allow a malicious SSH server to cause the supplied client to inappropriately trust the server.

Solution

Update to OpenSSH version 6.7 or later or apply the vendor patch.

See Also

http://thread.gmane.org/gmane.network.openssh.devel/20679

https://tools.ietf.org/html/rfc4255

https://seclists.org/oss-sec/2014/q1/663

Plugin Details

Severity: Medium

ID: 78655

File Name: openssh_sshfp_verification_weakness.nasl

Version: 1.9

Type: remote

Family: Misc.

Published: 10/23/2014

Updated: 4/27/2020

Dependencies: ssh_detect.nasl

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2014-2653

VPR

Risk Factor: Low

Score: 3.7

CVSS v2

Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.3

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

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

Vulnerability Information

CPE: cpe:/a:openbsd:openssh

Required KB Items: Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 10/21/2014

Vulnerability Publication Date: 3/24/2014

Reference Information

CVE: CVE-2014-2653

BID: 66459