CVE-2023-39950

2023-08-1421:15:13

CWE-20

[email protected]

web.nvd.nist.gov

efibootguard

uefi

boot loader

input validation

vulnerability

cve-2023-39950

nvd

6.1 Medium

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

5.1 Medium

AI Score

Confidence

High

0.0005 Low

EPSS

Percentile

17.4%

JSON

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.

Affected configurations

Vulners

NVD

Node

siemensefibootguardRange<0.15

VendorProductVersionCPE
siemensefibootguard*cpe:2.3:a:siemens:efibootguard:*:*:*:*:*:*:*:*

Vendor	Product	Version	CPE
siemens	efibootguard	*	cpe:2.3:a:siemens:efibootguard::::::::

CNA Affected

[
  {
    "vendor": "siemens",
    "product": "efibootguard",
    "versions": [
      {
        "version": "< 0.15",
        "status": "affected"
      }
    ]
  }
]