The shim package contains a first-stage UEFI boot loader that handles chaining to a trusted full boot loader under secure boot environments. Security Fix(es): * shim: RCE in http boot support may lead to Secure Boot bypass (CVE-2023-40547) * shim: Interger overflow leads to heap buffer overflow in verify_sbat_section on 32-bits systems (CVE-2023-40548) * shim: Out-of-bounds read printing error messages (CVE-2023-40546) * shim: Out-of-bounds read in verify_buffer_authenticode() malformed PE file (CVE-2023-40549) * shim: Out-of-bound read in verify_buffer_sbat() (CVE-2023-40550) * shim: out of bounds read when parsing MZ binaries (CVE-2023-40551) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.