efibootguard up to 0.14 bg_printenv memory corruption

Summaryinfo

A vulnerability classified as critical has been found in efibootguard up to 0.14. The impacted element is the function bg_printenv. This manipulation causes memory corruption. This vulnerability is registered as CVE-2023-39950. It is feasible to perform the attack on the physical device. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in efibootguard up to 0.14 and classified as critical. Affected by this vulnerability is the function bg_printenv. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was published 08/15/2023 as GHSA-j6pp-7g99-24m7. The advisory is shared at github.com. This vulnerability is known as CVE-2023-39950 since 08/07/2023. Technical details are known, but no exploit is available.

Upgrading to version 0.15 eliminates this vulnerability.

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Productinfo

Name

• efibootguard

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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