CVE-2021-20487
Published: 26 May 2021
Summary
CVE-2021-20487 is a critical-severity Improper Verification of Cryptographic Signature (CWE-347) vulnerability in Ibm Power9 System Firmware. Its CVSS base score is 9.1 (Critical).
Operationally, ranked at the 31.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-7905
Vulnerability details
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.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Requires verification of digital signatures using organization-approved certificates before installation, directly preventing improper verification of cryptographic signatures.
Component authenticity commonly depends on cryptographic signatures; the control enforces proper verification of those signatures.
PKI certificates under an approved policy require cryptographic signature verification on issuance and validation.
Requires cryptographic signatures on authoritative data and support for verifying the chain of trust.
Mandates verification of cryptographic signatures (e.g., DNSSEC RRSIG) on resolution responses, addressing missing or bypassed signature checks.
Integrity tools commonly rely on cryptographic signatures whose improper validation this weakness covers.
Authenticity validation commonly relies on cryptographic signature or certificate checks that this control enforces.