Critical severity · published May 26, 2021
CVE-2021-20487
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…
9.1
CVSS
0.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PS
Power9 System Firmware · Ibm
fw930.00 before fw930.30; fw940.00 before fw940.20; before fw950.00 · source: NVD
SL
Scale-out LC System Firmware · Ibm
before op940.20 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20487
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20487
VDB Entry
https://exchange.xforce.ibmcloud.com/vulnerabilities/197730
Vendor Advisory
https://www.ibm.com/support/pages/node/6455911
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