Detections
Analytics
Cisco UCS Manager UEFI Shell Secure Boot Bypass (cisco-sa-ucs-uefi-sb-bypass-eb6xC5GW)
high Nessus Plugin ID 348181
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Synopsis
The remote device is missing a vendor-supplied security patch.Description
According to its self-reported version, Cisco UCS Manager Software is affected by a vulnerability.- A vulnerability in the Unified Extensible Firmware Interface (UEFI) Shell implementation of Cisco UCS Servers and UCS-based appliances could allow an authenticated attacker with valid credentials for a user account with the role of user or admin or an unauthenticated attacker with physical access to an affected device to bypass UEFI Secure Boot validation checks and execute unauthorized software. This vulnerability is due to the availability of memory write commands in the UEFI Shell while UEFI Secure Boot is enabled on a device. An attacker could exploit this vulnerability by selecting the UEFI Shell boot option at boot time and using available shell commands to modify UEFI memory variables. A successful exploit could allow the attacker to manipulate the preboot environment, overwrite UEFI Secure Boot-related memory values, and execute unauthorized software on the affected device. (CVE-2026-20293)
Please see the included Cisco BID and Cisco Security Advisory for more information.
Solution
Upgrade to the relevant fixed version referenced in Cisco bug ID CSCwt77804.See Also
Plugin Details
Severity: High
ID: 348181
File Name: cisco-sa-ucs-uefi-sb-bypass-eb6xC5GW-ucs.nasl
Version: 1.3
Type: Remote
Family: CISCO
Published: 9/18/2026
Updated: 9/24/2026
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: High
Score: 7
Percentile: 98.05
CVSS v2
Risk Factor: Medium
Base Score: 6.2
Temporal Score: 4.9
Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:N
CVSS Score Source: CVE-2026-20293
CVSS v3
Risk Factor: High
Base Score: 7.1
Temporal Score: 6.4
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
Vulnerability Information
CPE: cpe:/a:cisco:unified_computing_system
Required KB Items: installed_sw/cisco_ucs_manager
Exploit Available: true
Exploit Ease: Exploits are available
Patch Publication Date: 9/8/2026
Vulnerability Publication Date: 9/8/2026
Reference Information
CVE: CVE-2026-20293