Cisco IOS-XE Zone-Based Firewall Feature Security Bypass (CSCun96847)

medium Nessus Plugin ID 91855
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The remote device is missing a vendor-supplied security patch.


According to its self-reported version, the Cisco IOS-XE software running on the remote device is affected by a security bypass vulnerability in the Zone-Based Firewall feature due to insufficient zone checking for traffic belonging to existing sessions. An unauthenticated, remote attacker can exploit this, by injecting spoofed traffic that matches existing connections, to bypass security access restrictions on the device and gain access to resources.


Apply the relevant patch referenced in the Cisco security advisory.
Alternatively, disable the Zone-Based Firewall feature according to the vendor advisory

See Also

Plugin Details

Severity: Medium

ID: 91855

File Name: cisco-CSCun96847-iosxe.nasl

Version: 1.8

Type: local

Family: CISCO

Published: 6/27/2016

Updated: 11/19/2019

Dependencies: cisco_ios_xe_version.nasl

Risk Information

CVSS Score Source: CVE-2014-2146


Risk Factor: Low

Score: 3.6


Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

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

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


Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Temporal Vector: E:U/RL:O/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: 5/29/2015

Vulnerability Publication Date: 5/29/2015

Reference Information

CVE: CVE-2014-2146