Cisco IOS XR Software for Cisco 8000 and NCS 540 Routers Image Verification Vulnerabilities (cisco-sa-ioxr-l-zNhcGCBt)

medium Nessus Plugin ID 147649
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Synopsis

The remote device is missing a vendor-supplied security patch

Description

According to its self-reported version, the Cisco IOS XR Software is affected by multiple vulnerabilities that allow an authenticated, local attacker to execute unsigned code during the boot process, as follows:

- A vulnerability in the GRUB boot loader of Cisco 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. (CVE-2021-1136)

- A vulnerability in the signing functions of ISO packaging of Cisco 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 with administrator privileges to execute unsigned code during the installation of an ISO on an affected device. (CVE-2021-1244)

Please see the included Cisco BIDs and Cisco Security Advisory for more information.

Solution

Upgrade to the relevant fixed version referenced in Cisco bug IDs CSCvr07463 and CSCvs70887.

See Also

http://www.nessus.org/u?ee8a7f16

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvr07463

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvs70887

Plugin Details

Severity: Medium

ID: 147649

File Name: cisco-sa-ioxr-l-zNhcGCBt-iosxr.nasl

Version: 1.6

Type: combined

Family: CISCO

Published: 3/11/2021

Updated: 4/8/2021

Dependencies: cisco_ios_xr_version.nasl

Risk Information

CVSS Score Source: CVE-2021-1136

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

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

CVSS v3

Risk Factor: Medium

Base Score: 6.7

Temporal Score: 5.8

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

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

Vulnerability Information

CPE: cpe:/o:cisco:ios_xr

Required KB Items: Host/Cisco/IOS-XR/Version

Exploit Ease: No known exploits are available

Patch Publication Date: 2/3/2021

Vulnerability Publication Date: 2/3/2021

Reference Information

CVE: CVE-2021-1136, CVE-2021-1244

IAVA: 2021-A-0062

CISCO-BUG-ID: CSCvr07463, CSCvs70887

CISCO-SA: cisco-sa-ioxr-l-zNhcGCBt