CVE-2019-1736: Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability

Published Sep 23, 2020
·
Updated

A vulnerability in the firmware of the Cisco UCS C-Series Rack Servers could allow an authenticated, physical attacker to bypass Unified Extensible Firmware Interface (UEFI) Secure Boot validation checks and load a compromised software image on an affected device. The vulnerability is due to improper validation of the server firmware upgrade images. An attacker could exploit this vulnerability by installing a server firmware version that would allow the attacker to disable UEFI Secure Boot. A successful exploit could allow the attacker to bypass the signature validation checks that are done by UEFI Secure Boot technology and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco.

Affected Software

23 affected components
All of the following
cisco Fmc1000-k9 Bios<4.0.1f.0
cisco Fmc1000-k9 Firmware<4.0.2h
All of the following
cisco Fmc2500-k9 Bios<4.0.1f.0
cisco Fmc2500-k9 Firmware<4.0.2h
All of the following
cisco Fmc4500-k9 Bios<4.0.1f.0
cisco Fmc4500-k9 Firmware<4.0.2h
All of the following
cisco Sns-3515-k9 Bios<4.0.2d
cisco Sns-3515-k9 Firmware<4.0.2h
All of the following
cisco Sns-3595-k9 Bios<4.0.2d
cisco Sns-3595-k9 Firmware<4.0.2h
All of the following
cisco Sns-3615-k9 Bios<4.0.1i
cisco Sns-3615-k9 Firmware<4.0.1g
All of the following
cisco Sns-3655-k9 Bios<4.0.1i
cisco Sns-3655-k9 Firmware<4.0.1g
All of the following
cisco Sns-3695-k9 Bios<4.0.1i
cisco Sns-3695-k9 Firmware<4.0.1g
All of the following
cisco Tg5004-k9 Bios<4.0.2d
cisco Tg5004-k9 Firmware<4.0.2h
All of the following
cisco Tg5004-k9-rf Bios<4.0.2d
cisco Tg5004-k9-rf Firmware<4.0.2h
cisco Identity Services Engine=2.4\(0.357\)
cisco Identity Services Engine=2.6\(0.156\)
Cisco Unified Computing System=3.2\(3h\)c

Event History

Sep 23, 2020
CVE Published
via MITRE·12:26 AM
Data Sourced
via MITRE·12:26 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2019-1736?

CVE-2019-1736 is a vulnerability in the firmware of the Cisco UCS C-Series Rack Servers that allows an authenticated, physical attacker to bypass UEFI Secure Boot validation checks and load a compromised software image on an affected device.

2

How can an attacker exploit CVE-2019-1736?

An attacker can exploit CVE-2019-1736 by physically accessing the Cisco UCS C-Series Rack Server and bypassing the UEFI Secure Boot validation checks.

3

What is the severity of CVE-2019-1736?

The severity of CVE-2019-1736 is medium, with a CVSS score of 6.6.

4

Which Cisco products are affected by CVE-2019-1736?

Cisco UCS C-Series Rack Servers, Cisco Identity Services Engine, and Cisco Unified Computing System are affected by CVE-2019-1736.

5

How can I fix CVE-2019-1736?

To fix CVE-2019-1736, Cisco recommends upgrading to the appropriate fixed version of the firmware or software.

Contact

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