Description
Shim is the initial UEFI bootloader that handles chaining to a trusted full
bootloader under secure boot environments.
A heap-based buffer overflow flaw was found the way shim parsed certain
IPv6 addresses. If IPv6 network booting was enabled, a malicious server
could supply a crafted IPv6 address that would cause shim to crash or,
potentially, execute arbitrary code. (CVE-2014-3676)
An out-of-bounds memory write flaw was found in the way shim processed
certain Machine Owner Keys (MOKs). A local attacker could potentially use
this flaw to execute arbitrary code on the system. (CVE-2014-3677)
An out-of-bounds memory read flaw was found in the way shim parsed certain
IPv6 packets. A specially crafted DHCPv6 packet could possibly cause shim
to crash, preventing the system from booting if IPv6 booting was enabled.
(CVE-2014-3675)