Cisco IOS XR RCE (cisco-sa-iosxr-pxe-unsign-code-exec-qAa78fD2)

High Nessus Plugin ID 142592

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VPR Score: 5.9

Synopsis

The remote device is missing a vendor-supplied security patch

Description

According to its self-reported version, IOS-XR is affected by a remote code execution vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader due to a failure to verify commands issued during a network boot. An unauthenticated, remote attacker can exploit this to execute unsigned code on an affected device.

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

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version

Solution

Upgrade to the relevant fixed version referenced in Cisco bug IDs CSCvi82550, CSCvq23340, CSCvq31064, CSCvu31574

See Also

http://www.nessus.org/u?fcce002a

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvi82550

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvq23340

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvq31064

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvu31574

Plugin Details

Severity: High

ID: 142592

File Name: cisco-sa-iosxr-pxe-unsign-code-exec-qAa78fD2-iosxr.nasl

Version: 1.6

Type: combined

Family: CISCO

Published: 2020/11/06

Updated: 2020/11/24

Dependencies: 71430

Configuration: Enable paranoid mode

Risk Information

Risk Factor: High

VPR Score: 5.9

CVSS Score Source: CVE-2020-3284

CVSS v2.0

Base Score: 9.3

Temporal Score: 6.9

Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 9.8

Temporal Score: 8.5

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:ios_xr

Required KB Items: Host/Cisco/IOS-XR/Version, Host/Cisco/IOS-XR/Model, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 2020/11/04

Vulnerability Publication Date: 2020/11/04

Reference Information

CVE: CVE-2020-3284