Multiple Cisco UCS-Based Products UEFI Secure Boot Bypass Vulnerability
Published Sep 23, 2020
6.6
MEDIUMCVSS 3.1
EPSS 0.25%
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.
Affected products
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||
|---|---|---|---|---|---|---|
| Cisco | Cisco Identity Services Engine Software | n/a |
|
Configuration 1
- < 4.0.1f.0
- < 4.0.2h
Configuration 2
- < 4.0.1f.0
- < 4.0.2h
Configuration 3
- < 4.0.1f.0
- < 4.0.2h
Configuration 4
- < 4.0.2d
- < 4.0.2h
Configuration 5
- < 4.0.2d
- < 4.0.2h
Configuration 6
- < 4.0.1i
- < 4.0.1g
Configuration 7
- < 4.0.1i
- < 4.0.1g
Configuration 8
- < 4.0.1i
- < 4.0.1g
Configuration 9
- < 4.0.2d
- < 4.0.2h
Configuration 10
- < 4.0.2d
- < 4.0.2h
Configuration 11
- 2.4\(0.357\)
- 2.6\(0.156\)
- 3.2\(3h\)c
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS:3.0/AV:P/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
AV:L/AC:M/Au:N/C:C/I:C/A:C
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Nov 13, 2024 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 4, 2026.
Score over time
2021-2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (9 key points)
Flat stretches are collapsed. Showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 4, 2026 | 0.25% (0.00247) | 14.46th | v5 (v2026.06.15) |
| Sep 20, 2026 | 0.25% (0.00247) | 16.25th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.04% (0.00044) | 12.95th | v3 (v2023.03.01) |
| May 25, 2024 | 0.04% (0.00044) | 12.27th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00044) | 10.26th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.89% (0.00885) | 27.89th | v2 (v2022.01.01) |
| Jan 6, 2022 | 1.84% (0.01840) | 47.32th | v1 |
| Jan 5, 2022 | 0.42% (0.00416) | 26.65th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.42% (0.00416) | 0.00th | v1 |
References (1)
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass vendor-advisoryx_refsource_CISCOPatchVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200219-ucs-boot-bypass | vendor-advisoryx_refsource_CISCOPatchVendor Advisory |
Change history (0)
No recorded changes yet.