Bartek Piekarski

**Name of the Vulnerable Software and Affected Versions** TrustedFirmware-M versions prior to 2.1.3 TrustedFirmware-M versions 2.2.x prior to 2.2.1 **Description** TrustedFirmware-M lacks length validation during a firmware upgrade. The Firmware Upgrade (FWU) module does not validate the length field of the Type-Length-Value (TLV) structure for dependent components against the maximum allowed size. If the length specified in the TLV exceeds the size of the buffer allocated on the stack, the FWU module will overwrite the buffer and potentially other stack data with the TLV’s value content. An attacker could exploit this by crafting a malicious TLV entry in the unprotected section of the MCUBoot upgrade image, manipulating the stack memory of the system during the upgrade process. **Recommendations** Upgrade to TrustedFirmware-M version 2.1.3 or later. Upgrade to TrustedFirmware-M version 2.2.1 or later.