CVE-2021-1136: Cisco IOS XR Software for Cisco 8000 Series Routers and Network Convergence System 540 Series Routers Image Verification Vulnerabilities

Published Feb 4, 2021
·
Updated

Multiple vulnerabilities in Cisco Network Convergence System (NCS) 540 Series Routers, only when running Cisco IOS XR NCS540L software images, and Cisco IOS XR Software for the Cisco 8000 Series Routers could allow an authenticated, local attacker to execute unsigned code during the boot process on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Affected Software

9 affected components
Cisco IOS XR<7.0.12
Cisco IOS XR>=7.1.0<7.2.1
Cisco 8201
Cisco 8202
Cisco 8808
Cisco 8812
Cisco 8818
Cisco IOS XR<7.2.1
Cisco Ncs 540

Event History

Feb 4, 2021
CVE Published
via MITRE·04:35 PM
Data Sourced
via MITRE·04:35 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the vulnerability ID of this Cisco Network Convergence System (NCS) 540 Series Routers vulnerability?

The vulnerability ID is CVE-2021-1136.

2

What is the severity of CVE-2021-1136?

The severity of CVE-2021-1136 is medium with a CVSS score of 6.7.

3

Which software versions are affected by CVE-2021-1136?

CVE-2021-1136 affects Cisco IOS XR NCS540L software images up to version 7.0.12 and Cisco IOS XR Software for the Cisco 8000 Series Routers up to version 7.2.1 (exclusive).

4

What can an authenticated, local attacker do with CVE-2021-1136?

An authenticated, local attacker could execute unsigned code during the boot process on the affected routers.

5

Is Cisco 8201/8202/8808/8812/8818 or Cisco Ncs 540 affected by CVE-2021-1136?

No, Cisco 8201/8202/8808/8812/8818 and Cisco Ncs 540 are not vulnerable to CVE-2021-1136.

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