CVE-2020-3284

Published Nov 6, 2020

Last updated 4 years ago

Overview

Description
A vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader for Cisco IOS XR 64-bit Software could allow an unauthenticated, remote attacker to execute unsigned code during the PXE boot process on an affected device. The PXE boot loader is part of the BIOS and runs over the management interface of hardware platforms that are running Cisco IOS XR Software only. The vulnerability exists because internal commands that are issued when the PXE network boot process is loading a software image are not properly verified. An attacker could exploit this vulnerability by compromising the PXE boot server and replacing a valid software image with a malicious one. Alternatively, the attacker could impersonate the PXE boot server and send a PXE boot reply with a malicious file. A successful exploit could allow the attacker to execute unsigned code on the affected device. Note: To fix this vulnerability, both the Cisco IOS XR Software and the BIOS must be upgraded. The BIOS code is included in Cisco IOS XR Software but might require additional installation steps. For further information, see the Fixed Software section of this advisory.
Source
ykramarz@cisco.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
9.8
Impact score
5.9
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
CRITICAL

CVSS 3.0

Type
Secondary
Base score
8.1
Impact score
5.9
Exploitability score
2.2
Vector string
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
9.3
Impact score
10
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:C/I:C/A:C

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo
ykramarz@cisco.com
CWE-284

Social media

Hype score
Not currently trending

Configurations