CVSS3
Attack Vector
PHYSICAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
LOW
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:L
AI Score
Confidence
High
EPSS
Percentile
24.2%
efibootguard is a simple UEFI boot loader with support for safely switching between current and updated partition sets. Insufficient or missing validation and sanitization of input from untrustworthy bootloader environment files can cause crashes and probably also code injections into bg_setenv
) or programs using libebgenv
. This is triggered when the affected components try to modify a manipulated environment, in particular its user variables. Furthermore, bg_printenv
may crash over invalid read accesses or report invalid results. Not affected by this issue is EFI Boot Guard’s bootloader EFI binary. EFI Boot Guard release v0.15 contains required patches to sanitize and validate the bootloader environment prior to processing it in userspace. Its library and tools should be updated, so should programs statically linked against it. An update of the bootloader EFI executable is not required. The only way to prevent the issue with an unpatched EFI Boot Guard version is to avoid accesses to user variables, specifically modifications to them.
[
{
"vendor": "siemens",
"product": "efibootguard",
"versions": [
{
"version": "< 0.15",
"status": "affected"
}
]
}
]
CVSS3
Attack Vector
PHYSICAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
LOW
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:L
AI Score
Confidence
High
EPSS
Percentile
24.2%