CVE-2019-1736

Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability

Severity Score

6.6

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Una vulnerabilidad en el firmware de Cisco UCS C-Series Rack Servers, podría permitir a un atacante físico autenticado omitir las comprobaciones de validación de Unified Extensible Firmware Interface (UEFI) Secure Boot y cargar una imagen de software comprometida en un dispositivo afectado. La vulnerabilidad es debido a una comprobación inapropiada de las imágenes de actualización del firmware del servidor. Un atacante podría explotar esta vulnerabilidad mediante la instalación una versión de firmware del servidor que le permitiría deshabilitar el UEFI Secure Boot. Una explotación con éxito podría permitir al atacante omitir las comprobaciones de validación de firmas que realiza la tecnología UEFI Secure Boot y cargar una imagen de software comprometida en el dispositivo afectado. Una imagen de software comprometida es cualquier imagen de software que no haya sido firmada digitalmente por Cisco

*Credits: N/A

CVSS Scores

Attack Vector

Physical

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Physical

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2018-12-06 CVE Reserved
2020-09-23 CVE Published
2023-03-08 EPSS Updated
2024-09-16 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-347: Improper Verification of Cryptographic Signature

CAPEC

References (1)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass	2020-10-23

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Cisco Search vendor "Cisco"		Fmc1000-k9 Bios Search vendor "Cisco" for product "Fmc1000-k9 Bios"				< 4.0.1f.0 Search vendor "Cisco" for product "Fmc1000-k9 Bios" and version " < 4.0.1f.0"		-		Affected
Cisco Search vendor "Cisco"		Fmc1000-k9 Firmware Search vendor "Cisco" for product "Fmc1000-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Fmc1000-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Fmc2500-k9 Bios Search vendor "Cisco" for product "Fmc2500-k9 Bios"				< 4.0.1f.0 Search vendor "Cisco" for product "Fmc2500-k9 Bios" and version " < 4.0.1f.0"		-		Affected
Cisco Search vendor "Cisco"		Fmc2500-k9 Firmware Search vendor "Cisco" for product "Fmc2500-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Fmc2500-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Fmc4500-k9 Bios Search vendor "Cisco" for product "Fmc4500-k9 Bios"				< 4.0.1f.0 Search vendor "Cisco" for product "Fmc4500-k9 Bios" and version " < 4.0.1f.0"		-		Affected
Cisco Search vendor "Cisco"		Fmc4500-k9 Firmware Search vendor "Cisco" for product "Fmc4500-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Fmc4500-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Sns-3515-k9 Bios Search vendor "Cisco" for product "Sns-3515-k9 Bios"				< 4.0.2d Search vendor "Cisco" for product "Sns-3515-k9 Bios" and version " < 4.0.2d"		-		Affected
Cisco Search vendor "Cisco"		Sns-3515-k9 Firmware Search vendor "Cisco" for product "Sns-3515-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Sns-3515-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Sns-3595-k9 Bios Search vendor "Cisco" for product "Sns-3595-k9 Bios"				< 4.0.2d Search vendor "Cisco" for product "Sns-3595-k9 Bios" and version " < 4.0.2d"		-		Affected
Cisco Search vendor "Cisco"		Sns-3595-k9 Firmware Search vendor "Cisco" for product "Sns-3595-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Sns-3595-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Sns-3615-k9 Bios Search vendor "Cisco" for product "Sns-3615-k9 Bios"				< 4.0.1i Search vendor "Cisco" for product "Sns-3615-k9 Bios" and version " < 4.0.1i"		-		Affected
Cisco Search vendor "Cisco"		Sns-3615-k9 Firmware Search vendor "Cisco" for product "Sns-3615-k9 Firmware"				< 4.0.1g Search vendor "Cisco" for product "Sns-3615-k9 Firmware" and version " < 4.0.1g"		-		Affected
Cisco Search vendor "Cisco"		Sns-3655-k9 Bios Search vendor "Cisco" for product "Sns-3655-k9 Bios"				< 4.0.1i Search vendor "Cisco" for product "Sns-3655-k9 Bios" and version " < 4.0.1i"		-		Affected
Cisco Search vendor "Cisco"		Sns-3655-k9 Firmware Search vendor "Cisco" for product "Sns-3655-k9 Firmware"				< 4.0.1g Search vendor "Cisco" for product "Sns-3655-k9 Firmware" and version " < 4.0.1g"		-		Affected
Cisco Search vendor "Cisco"		Sns-3695-k9 Bios Search vendor "Cisco" for product "Sns-3695-k9 Bios"				< 4.0.1i Search vendor "Cisco" for product "Sns-3695-k9 Bios" and version " < 4.0.1i"		-		Affected
Cisco Search vendor "Cisco"		Sns-3695-k9 Firmware Search vendor "Cisco" for product "Sns-3695-k9 Firmware"				< 4.0.1g Search vendor "Cisco" for product "Sns-3695-k9 Firmware" and version " < 4.0.1g"		-		Affected
Cisco Search vendor "Cisco"		Tg5004-k9 Bios Search vendor "Cisco" for product "Tg5004-k9 Bios"				< 4.0.2d Search vendor "Cisco" for product "Tg5004-k9 Bios" and version " < 4.0.2d"		-		Affected
Cisco Search vendor "Cisco"		Tg5004-k9 Firmware Search vendor "Cisco" for product "Tg5004-k9 Firmware"				< 4.0.2h Search vendor "Cisco" for product "Tg5004-k9 Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Tg5004-k9-rf Bios Search vendor "Cisco" for product "Tg5004-k9-rf Bios"				< 4.0.2d Search vendor "Cisco" for product "Tg5004-k9-rf Bios" and version " < 4.0.2d"		-		Affected
Cisco Search vendor "Cisco"		Tg5004-k9-rf Firmware Search vendor "Cisco" for product "Tg5004-k9-rf Firmware"				< 4.0.2h Search vendor "Cisco" for product "Tg5004-k9-rf Firmware" and version " < 4.0.2h"		-		Affected
Cisco Search vendor "Cisco"		Identity Services Engine Search vendor "Cisco" for product "Identity Services Engine"				2.4\(0.357\) Search vendor "Cisco" for product "Identity Services Engine" and version "2.4\(0.357\)"		-		Affected
Cisco Search vendor "Cisco"		Identity Services Engine Search vendor "Cisco" for product "Identity Services Engine"				2.6\(0.156\) Search vendor "Cisco" for product "Identity Services Engine" and version "2.6\(0.156\)"		-		Affected
Cisco Search vendor "Cisco"		Unified Computing System Search vendor "Cisco" for product "Unified Computing System"				3.2\(3h\)c Search vendor "Cisco" for product "Unified Computing System" and version "3.2\(3h\)c"		-		Affected