CVE-2020-3404: Cisco IOS XE Software Consent Token Bypass Vulnerability

Published Sep 24, 2020
·
Updated

A vulnerability in the persistent Telnet/Secure Shell (SSH) CLI of Cisco IOS XE Software could allow an authenticated, local attacker to gain shell access on an affected device and execute commands on the underlying operating system (OS) with root privileges. The vulnerability is due to insufficient enforcement of the consent token in authorizing shell access. An attacker could exploit this vulnerability by authenticating to the persistent Telnet/SSH CLI on an affected device and requesting shell access. A successful exploit could allow the attacker to gain shell access on the affected device and execute commands on the underlying OS with root privileges.

Affected Software

128 affected components
Cisco IOS XE=16.11.1
Cisco 1100-4g Integrated Services Router
Cisco 1100-4gltegb Integrated Services Router
Cisco 1100-4gltena Integrated Services Router
Cisco 1100-4p Integrated Services Router
Cisco 1100-6g Integrated Services Router
Cisco 1100-8p Integrated Services Router
Cisco 1100-lte Integrated Services Router
Cisco 1100 Integrated Services Router
Cisco 1101-4p Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1109-2p Integrated Services Router
Cisco 1109-4p Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x-8p Integrated Services Router
Cisco 1111x Integrated Services Router
Cisco 111x Integrated Services Router
Cisco 1120 Integrated Services Router
Cisco 1160 Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4331 Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4451 Integrated Services Router
Cisco 4461 Integrated Services Router
Cisco Asr 1000-x
Cisco Asr 1001
Cisco Asr 1001-x
Cisco Asr 1002
Cisco Asr 1002-x
Cisco Asr 1004
Cisco Asr 1006
Cisco Asr 1013
Cisco Asr1001-hx
Cisco Asr1001-hx-rf
Cisco Asr1001-x-rf
Cisco Asr1001-x-ws
Cisco Asr1002-hx
Cisco Asr1002-hx-rf
Cisco Asr1002-hx-ws
Cisco Asr1002-x-rf
Cisco Asr1002-x-ws
Cisco Catalyst 9800-40
Cisco Catalyst 9800-80
Cisco Catalyst 9800-cl
Cisco Catalyst 9800-l
Cisco Catalyst 9800-l-c
Cisco Catalyst 9800-l-f
Cisco Catalyst C9200-24p
Cisco Catalyst C9200-24t
Cisco Catalyst C9200-48p
Cisco Catalyst C9200-48t
Cisco Catalyst C9200l-24p-4g
Cisco Catalyst C9200l-24p-4x
Cisco Catalyst C9200l-24pxg-2y
Cisco Catalyst C9200l-24pxg-4x
Cisco Catalyst C9200l-24t-4g
Cisco Catalyst C9200l-24t-4x
Cisco Catalyst C9200l-48p-4g
Cisco Catalyst C9200l-48p-4x
Cisco Catalyst C9200l-48pxg-2y
Cisco Catalyst C9200l-48pxg-4x
Cisco Catalyst C9200l-48t-4g
Cisco Catalyst C9200l-48t-4x
Cisco Catalyst C9300-24p
Cisco Catalyst C9300-24s
Cisco Catalyst C9300-24t
Cisco Catalyst C9300-24u
Cisco Catalyst C9300-24ux
Cisco Catalyst C9300-48p
Cisco Catalyst C9300-48s
Cisco Catalyst C9300-48t
Cisco Catalyst C9300-48u
Cisco Catalyst C9300-48un
Cisco Catalyst C9300-48uxm
Cisco Catalyst C9300l-24p-4g
Cisco Catalyst C9300l-24p-4x
Cisco Catalyst C9300l-24t-4g
Cisco Catalyst C9300l-24t-4x
Cisco Catalyst C9300l-48p-4g
Cisco Catalyst C9300l-48p-4x
Cisco Catalyst C9300l-48t-4g
Cisco Catalyst C9300l-48t-4x
Cisco Catalyst C9404r
Cisco Catalyst C9407r
Cisco Catalyst C9410r
Cisco Catalyst C9500-12q
Cisco Catalyst C9500-16x
Cisco Catalyst C9500-24q
Cisco Catalyst C9500-24y4c
Cisco Catalyst C9500-32c
Cisco Catalyst C9500-32qc
Cisco Catalyst C9500-40x
Cisco Catalyst C9500-48y4c
Cisco Csr 1000v
Cisco Ws-c3650-12x48uq
Cisco Ws-c3650-12x48ur
Cisco Ws-c3650-12x48uz
Cisco Ws-c3650-24pd
Cisco Ws-c3650-24pdm
Cisco Ws-c3650-24ps
Cisco Ws-c3650-24td
Cisco Ws-c3650-24ts
Cisco Ws-c3650-48fd
Cisco Ws-c3650-48fq
Cisco Ws-c3650-48fqm
Cisco Ws-c3650-48fs
Cisco Ws-c3650-48pd
Cisco Ws-c3650-48pq
Cisco Ws-c3650-48ps
Cisco Ws-c3650-48td
Cisco Ws-c3650-48tq
Cisco Ws-c3650-48ts
Cisco Ws-c3650-8x24uq
Cisco WS-C3850
Cisco Ws-c3850-12s
Cisco Ws-c3850-12x48u
Cisco Ws-c3850-12xs
Cisco Ws-c3850-24p
Cisco Ws-c3850-24s
Cisco Ws-c3850-24t
Cisco Ws-c3850-24u
Cisco Ws-c3850-24xs
Cisco Ws-c3850-24xu
Cisco Ws-c3850-48f
Cisco Ws-c3850-48p
Cisco Ws-c3850-48t
Cisco Ws-c3850-48u
Cisco Ws-c3850-48xs

Event History

Sep 24, 2020
CVE Published
via MITRE·06:02 PM
Data Sourced
via MITRE·06:02 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2020-3404?

CVE-2020-3404 has been classified with a high severity rating due to its potential to allow authenticated attackers to execute commands with root privileges on affected devices.

2

How do I fix CVE-2020-3404?

To fix CVE-2020-3404, it is recommended to update your Cisco IOS XE software to the latest version that addresses this vulnerability.

3

Which Cisco devices are affected by CVE-2020-3404?

CVE-2020-3404 primarily affects Cisco IOS XE Software version 16.11.1.

4

Can CVE-2020-3404 be exploited remotely?

No, CVE-2020-3404 requires authenticated local access, meaning an attacker must have local access to the device to exploit the vulnerability.

5

What are the potential impacts of CVE-2020-3404?

The potential impacts of CVE-2020-3404 include unauthorized access to the underlying operating system and execution of arbitrary commands with elevated privileges.

Contact

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