Cisco IOS XE SSHv2 RSA-Based User Authentication Bypass (CSCus73013)

high Nessus Plugin ID 86250

Synopsis

The remote device is missing a vendor-supplied security patch.

Description

The remote Cisco IOS XE device is missing a vendor-supplied security patch, and is configured for SSHv2 RSA-based user authentication. It is, therefore, affected by a flaw in the SSHv2 protocol implementation of the public key authentication method. An unauthenticated, remote attacker can exploit this, via a crafted private key, to bypass authentication mechanisms. In order to exploit this vulnerability an attacker must know a valid username configured for RSA-based user authentication and the public key configured for that user.

Solution

Upgrade to the relevant fixed version referenced in Cisco bug ID CSCus73013.

See Also

http://www.nessus.org/u?f2660861

Plugin Details

Severity: High

ID: 86250

File Name: cisco-sa-20150923-sshpk-iosxe.nasl

Version: 1.13

Type: local

Family: CISCO

Published: 10/2/2015

Updated: 11/20/2019

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 9.3

Temporal Score: 6.9

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

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

Vulnerability Information

CPE: cpe:/o:cisco:ios_xe

Required KB Items: Host/Cisco/IOS-XE/Version

Exploit Ease: No known exploits are available

Patch Publication Date: 9/23/2015

Vulnerability Publication Date: 9/23/2015

Reference Information

CVE: CVE-2015-6280

CISCO-BUG-ID: CSCus73013

CISCO-SA: cisco-sa-20150923-sshpk