CVE-2024-32883

MCUboot Injection attack of unprotected TLV values

Published Apr 26, 2024 CVSS 3.1 · 7.7 High EPSS < 1% KEV · Not listed

Description

MCUboot is a secure bootloader for 32-bits microcontrollers. MCUboot uses a TLV (tag-length-value) structure to represent the meta data associated with an image. The TLVs themselves are divided into two sections, a protected and an unprotected section. The protected TLV entries are included as part of the image signature to avoid tampering. However, the code does not distinguish which TLV entries should be protected or not, so it is possible for an attacker to add unprotected TLV entries that should be protected. Currently, the primary protected TLV entries should be the dependency indication, and the boot record. An injected dependency value would primarily result in an otherwise acceptable image being rejected. A boot record injection could allow fields in a later attestation record to include data not intended, which could cause an image to appear to have properties that it should not have. As a workaround, disable the boot record functionality.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

mcu-tools

mcuboot

affected

Version	Status	Constraints
`<= 1.11.0`	affected	—

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Advisories

Source	ID	Title
EUVD	EUVD-2024-30657	MCUboot is a secure bootloader for 32-bits microcontrollers. MCUboot uses a TLV (tag-length-value) structure to represent the meta data associated with an image. The TLVs themselves are divided into two sections, a protected and an unprotected section. The protected TLV entries are included as part of the image signature to avoid tampering. However, the code does not distinguish which TLV entries should be protected or not, so it is possible for an attacker to add unprotected TLV entries that should be protected. Currently, the primary protected TLV entries should be the dependency indication, and the boot record. An injected dependency value would primarily result in an otherwise acceptable image being rejected. A boot record injection could allow fields in a later attestation record to include data not intended, which could cause an image to appear to have properties that it should not have. As a workaround, disable the boot record functionality.