CVE-2020-3118: Cisco IOS XR Software Discovery Protocol Format String Vulnerability

Published Feb 5, 2020
·
Updated

A vulnerability in the Cisco Discovery Protocol implementation for Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device. The vulnerability is due to improper validation of string input from certain fields in Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to cause a stack overflow, which could allow the attacker to execute arbitrary code with administrative privileges on an affected device. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

Other sources

Cisco IOS XR improperly validates string input from certain fields in Cisco Discovery Protocol messages. Exploitation could allow an unauthenticated, adjacent attacker to execute code with administrative privileges or cause a reload on an affected device.

CISA

Affected Software

95 affected components
Cisco IOS XR
Cisco IOS XR>=6.6.0<6.6.12
Cisco IOS XR>=7.0.0<7.0.2
All of the following
Cisco IOS XR=6.5.3
Any of the following
Cisco Asr 9000v
Cisco Asr 9001
Cisco Asr 9006
Cisco Asr 9010
Cisco Asr 9901
Cisco Asr 9904
Cisco Asr 9906
Cisco Asr 9910
Cisco Asr 9912
Cisco Asr 9922
Cisco Ncs 540-12z20g-sys-a
Cisco Ncs 540-12z20g-sys-d
Cisco Ncs 540-24z8q2c-sys
Cisco Ncs 540-28z4c-sys-a
Cisco Ncs 540-28z4c-sys-d
Cisco Ncs 540-acc-sys
Cisco Ncs 540x-12z16g-sys-a
Cisco Ncs 540x-12z16g-sys-d
Cisco Ncs 540x-16z4g8q2c-a
Cisco Ncs 540x-16z4g8q2c-d
Cisco Ncs 540x-acc-sys
Cisco Ncs 5501
Cisco Ncs 5501-se
Cisco Ncs 5502
Cisco Ncs 5502-se
Cisco Ncs 5508
Cisco Ncs 5516
Cisco Xrv 9000
All of the following
Cisco IOS XR=5.2.5
Any of the following
Cisco Ncs 6000
Cisco Ncs 6008
All of the following
Cisco IOS XR=6.4.2
Any of the following
Cisco ASR 9000
Cisco Asr 9000v
Cisco Asr 9001
Cisco Asr 9006
Cisco Asr 9010
Cisco Asr 9901
Cisco ASR 9903
Cisco Asr 9904
Cisco Asr 9906
Cisco Asr 9910
Cisco Asr 9912
Cisco Asr 9920
Cisco Asr 9922
Cisco Crs-x
All of the following
Cisco IOS XR=6.6.25
Cisco Ncs 560
All of the following
Cisco IOS XR=7.0.1
Cisco Ncs 540l
Cisco IOS XR=6.5.3
Cisco Asr 9000v
Cisco Asr 9001
Cisco Asr 9006
Cisco Asr 9010
Cisco Asr 9901
Cisco Asr 9904
Cisco Asr 9906
Cisco Asr 9910
Cisco Asr 9912
Cisco Asr 9922
Cisco Ncs 540-12z20g-sys-a
Cisco Ncs 540-12z20g-sys-d
Cisco Ncs 540-24z8q2c-sys
Cisco Ncs 540-28z4c-sys-a
Cisco Ncs 540-28z4c-sys-d
Cisco Ncs 540-acc-sys
Cisco Ncs 540x-12z16g-sys-a
Cisco Ncs 540x-12z16g-sys-d
Cisco Ncs 540x-16z4g8q2c-a
Cisco Ncs 540x-16z4g8q2c-d
Cisco Ncs 540x-acc-sys
Cisco Ncs 5501
Cisco Ncs 5501-se
Cisco Ncs 5502
Cisco Ncs 5502-se
Cisco Ncs 5508
Cisco Ncs 5516
Cisco Xrv 9000
Cisco IOS XR=5.2.5
Cisco Ncs 6000
Cisco Ncs 6008
Cisco IOS XR=6.4.2
Cisco ASR 9000
Cisco ASR 9903
Cisco Asr 9920
Cisco Crs-x
Cisco IOS XR=6.6.25
Cisco Ncs 560
Cisco IOS XR=7.0.1
Cisco Ncs 540l

Event History

Feb 5, 2020
CVE Published
via MITRE·05:40 PM
Data Sourced
via MITRE·05:40 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM
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Frequently Asked Questions

1

What is CVE-2020-3118?

CVE-2020-3118 is a vulnerability in the Cisco Discovery Protocol implementation for Cisco IOS XR Software.

2

How does CVE-2020-3118 affect Cisco IOS XR Software?

CVE-2020-3118 could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device.

3

Which versions of Cisco IOS XR Software are affected by CVE-2020-3118?

Versions between 6.6.0 to 6.6.12 and between 7.0.0 to 7.0.2 of Cisco IOS XR Software are affected by CVE-2020-3118.

4

What is the severity of CVE-2020-3118?

CVE-2020-3118 has a severity rating of 8.8 (high).

5

How can I fix CVE-2020-3118 in Cisco IOS XR Software?

To fix CVE-2020-3118, it is recommended to update to a fixed software version as mentioned in the Cisco Security Advisory.

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