CVE-2021-20487
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and...
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.
- Record
CVE-2021-20487- CVSS 3.0
- 8.0 High
CVSS:3.0/AV:N/UI:N/I:H/AC:H/PR:H/S:C/A:H/C:H/E:U/RL:O/RC:C - Updated
- 2026-11-02
EUVDEUVD-2021-7905
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.
- Record
EUVD-2021-7905- CVSS 3.0
- 8.0 High
CVSS:3.0/AV:N/UI:N/I:H/AC:H/PR:H/S:C/A:H/C:H/E:U/RL:O/RC:C - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gwjp-78rh-pcgc No score
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and...
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.
- Record
GHSA-gwjp-78rh-pcgc- Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.
- Record
CVE-2021-20487- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - CVSS 3.0
- 8.0 High
CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H - CVSS 2.0
- 6.5 Medium
AV:N/AC:L/Au:S/C:P/I:P/A:P - Weakness
- CWE-347
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20487 is a high vulnerability (CVSS 8.0) in Ibm Power 9 Systems, published May 26, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.68%, the 52nd percentile. No source names a fixed version.