CVE-2020-3503: Cisco IOS XE Software Guest Shell Unauthorized File System Access Vulnerability

Published Sep 24, 2020
·
Updated

A vulnerability in the file system permissions of Cisco IOS XE Software could allow an authenticated, local attacker to obtain read and write access to critical configuration or system files. The vulnerability is due to insufficient file system permissions on an affected device. An attacker could exploit this vulnerability by connecting to an affected device's guest shell, and accessing or modifying restricted files. A successful exploit could allow the attacker to view or modify restricted information or configurations that are normally not accessible to system administrators.

Affected Software

256 affected components
Cisco IOS XE=16.12.1
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
All of the following
Cisco IOS XE=16.12.1
Any of the following
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·05:51 PM
Data Sourced
via MITRE·05:51 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2020-3503?

CVE-2020-3503 is assessed as having a high severity level due to the potential for unauthorized access to sensitive configuration or system files.

2

How do I fix CVE-2020-3503?

To mitigate CVE-2020-3503, ensure that you upgrade to the fixed version of Cisco IOS XE Software that addresses the inadequate file system permissions.

3

Who is affected by CVE-2020-3503?

CVE-2020-3503 affects devices running Cisco IOS XE Software version 16.12.1.

4

What kind of access does CVE-2020-3503 allow an attacker?

CVE-2020-3503 allows an authenticated local attacker to obtain read and write access to critical configuration or system files.

5

Is there a workaround for CVE-2020-3503?

There are no documented workarounds for CVE-2020-3503, so upgrading to a secure version is critical.

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