Cisco UCS C-Series Rack Servers Signature Validation Firmware signature verification

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.9	$0-$5k	0.00

A vulnerability was found in Cisco UCS C-Series Rack Servers (Virtualization Software) (version unknown). It has been classified as critical. This affects an unknown function of the component Signature Validation. The manipulation as part of a Firmware leads to a signature verification vulnerability. CWE is classifying the issue as CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 09/23/2020 as cisco-sa-20200219-ucs-boot-byp as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. This vulnerability is uniquely identified as CVE-2019-1736 since 12/06/2018. Attacking locally is a requirement. The successful exploitation requires a authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading eliminates this vulnerability.

See 150355 for similar entry.

Productinfo

Type

Virtualization Software

Vendor

Cisco

Name

UCS C-Series Rack Servers

License

commercial

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.2
VulDB Temp Score: 5.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.2
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
unlock	unlock	unlock	unlock	unlock	unlock
unlock	unlock	unlock	unlock	unlock	unlock
unlock	unlock	unlock	unlock	unlock	unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Signature verification
CWE: CWE-347 / CWE-345
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	unlock	unlock	unlock	unlock
Today	unlock	unlock	unlock	unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/06/2018 🔍
09/23/2020 +657 days 🔍
09/23/2020 +0 days 🔍
09/23/2020 +0 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20200219-ucs-boot-byp
Status: Confirmed

CVE: CVE-2019-1736 (🔍)
See also: 🔍

Entryinfo

Created: 09/23/2020 12:04
Updated: 09/23/2020 12:09
Changes: 09/23/2020 12:04 (41), 09/23/2020 12:09 (12)
Complete: 🔍