PT-2020-1825 · Cisco · Cisco Ucs C-Series Rack Servers

Emre Demirors · Published 2020-02-19 · Updated 2020-10-23 · CVE-2019-1736

Positive Technologies (AI Summary)

CVSS v2.0

6.9

Medium

Base vector

AV:L/AC:M/Au:N/C:C/I:C/A:C

Name of the Vulnerable Software and Affected Versions Cisco UCS C-Series Rack Servers (affected versions not specified)

Description 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.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Improper Verification of Cryptographic Signature

Weakness Enumeration

CWE-347

Related Identifiers

BDU:2020-01089

CVE-2019-1736

Affected Products

Cisco Ucs C-Series Rack Servers

References · 5

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2019-1736 · Vendor Advisory
• https://bdu.fstec.ru/vul/2020-01089 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2019-1736 · Security Note
• https://t.me/cibsecurity/14824 · Telegram Post