Linux Kernel Vulnerability Affecting Secure Boot Mechanisms

CVE-2022-21505

Summary

In the Linux kernel, a security flaw exists related to the use of Integrity Measurement Architecture (IMA) appraisal with the boot parameter 'ima_appraise=log'. If this parameter is set and Secure Boot is either disabled or not available, the system's lockdown can potentially be exploited using the kexec command. While IMA provides protection by preventing the setting of 'ima_appraise=log' when Secure Boot is enabled, this safeguard does not extend to scenarios where lockdown is operational without Secure Boot. This situation raises significant concerns regarding the confidentiality, integrity, and availability of the affected systems, as malicious actors may exploit this vulnerability to bypass security mechanisms.

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