STM32 MCUs Security

Hello,After spending several days investigating this topic and reviewing all the documentation I could find, I am still completely stuck on how to proceed with implementing STiROT + OEMuROT on my STM32H7S3.An important point is that I am trying to add this security architecture to a project that is already at a fairly advanced stage of development. The project was originally built on top of the XIP template provided by ST:https://github.com/STMicroelectronics/STM32CubeH7RS/tree/main/Projects/NUCLEO-H7S3L8/Templates/Template_XIP The difficulty comes from the fact that, in the XIP context, the project only includes these layers:AppliBootExtMemLoaderAs a first step, I imported ROT_Provisioning into the project in a separate folder. However, I

Hi!My application requires NIST-compliant random number generation, and I see some unclear/contradicting info on the Reference Manual, the AN4230 application note, and the public NIST certificate. My MCU is STM32H563ZI.- Reference Manual: https://www.st.com/resource/en/reference_manual/rm0481-stm32h52333xx-stm32h56263xx-and-stm32h573xx-armbased-32bit-mcus-stmicroelectronics.pdf- AN4230: https://www.st.com/resource/en/application_note/an4230-introduction-to-random-number-generation-validation-using-the-nist-statistical-

HiI have STM32H563 Nucleo board which is in closed state with DA_Config.obk not programmed, And the trust zone disabled. This was done by mistake, Is there a way to do regression on it.Operations Done on the device.1.Done the regression2.Set the product state to provisioning3.Programmed OEMiRoT_Config.obk4.Set the device to closed state.Logs from ST32Cube programmer on DA Discovery10:40:20 : STM32CubeProgrammer API v2.19.0 | Windows-64Bits10:44:38 : Start Debug Authentication Sequence10:44:38 : SDMOpen : 624 : open : SDM API v1.010:44:38 : SDMOpen : 625 : open : SDM Library version v1.2.010:44:38 : open_comms : 513 : open : Asserting target reset10:44:38 : open_comms : 517 : open : Writing magic number10:44:38 : open_comms : 537 : open : De-asserting target reset10:44:38 : open_comms : 584 : open : Communication with the target established success

 Now that that the CRA dates are near, why is there isn't a forum for regulatory compliance and CRA specific questions ?For example, which products STM offers now will not be CRA compliant ? This is important as those products would have to be revised or removed from the market.For example an STM32F072 would still meet requirement 1. as the main controller of the product with our without an RF/network connection (via UART/I2C etc..)  or 2. as a peripheral  connected to the main MPU (indirect) which connects with LAN or WIFI to outside world     

On an STM32H563, I am trying to write the OBkey1 data.I have successfully set the product state to provisioning (0x17) with: FLASH_OBProgramInitTypeDef optionBytes; HAL_FLASHEx_OBGetConfig(&optionBytes); HAL_FLASH_Unlock(); HAL_FLASH_OB_Unlock(); optionBytes.OptionType = OPTIONBYTE_PROD_STATE; optionBytes.ProductState = OB_PROD_STATE_PROVISIONING; HAL_FLASHEx_OBProgram(&optionBytes); HAL_FLASH_OB_Launch(); HAL_FLASH_OB_Lock();Now, when I try to write too OBKey1 with: uint32_t dataAddr = 0x20050000; memcpy ((void*)dataAddr, source, 0x60); RSSLIB_DataProvisioningConf_t * pConfig = (RSSLIB_DataProvisioningConf_t *)0x20050100; pConfig->pSource = (uint32_t*)dataAddr; pConfig->pDestination = (uint32_t*)0xffd0100; pConfig->Size = 0x60; pConfig->DoEncryption = 0xCACA0AA0U; pConfig->Crc = 0; HAL_FLASHEx_OBK_Unlock(); provis

Hi everyone,I’m using the B‑U585I‑IOT02A development board for an IoT project. The onboard STSAFE‑A110 secure element comes pre‑provisioned with a default key and certificate, but for my application I need to:Provision my own keypair and certificate, andOptionally add additional keys or certificates into unused STSAFE slots (for testing or multi‑cloud use).I couldn’t find a clear step‑by‑step guide for:Generating and injecting a custom keypairUploading a custom certificate chainAdding extra keys/certificates to new STSAFE slotsWhether CubeProgrammer or Secure Manager scripts support provisioning user keysIs there any official documentation, example project, or provisioning tool that explains how to do this on the B‑U585I‑IOT02A?Any guidance or links would be greatly appreciated.Thank you!

Hello together,I search for a solution to put calibration data in a NS area.Background Information:we are using STM35H573 with STM secure manager.we use an ethernet Rest API to update Application including request install and so onNow I want to use the same Rest API to update configuration data. The BIN file shall be signed like a normal application. The behavior should be more or less the same: Restart µC, SM checks validity; app will be started,...I have read um3254 but I do not understand the section with large profile.I have read something about ITS, but I think this is not the solution I need. The calibration data must not be stored in the trusted area. They shall only validated bei the SM during update or startup. Thanks for joining this topic. Br Sebastian 

Hi,I added some follow-up questions to a message but I'm not sure if anyone will notice as I had already clicked "Accepted Solution" :-https://community.st.com/t5/stm32-mcus-security/stm32h5-simple-security-settings/m-p/885235/thread-id/9530#M9531Copying the questions regarding setting H5 security to be more like G4 RDP setting.1) Since the regression to open performs a full chips erase, am I right in thinking that we can use a common and not secure password? i.e. Revealing the password does not allow access to the firmware.2) Can I perform all of the steps listed, from my bootloader firmware? As far as I can see, the changes to product state just require a write to write to an option byte. I have yet to find the part of the reference manual that describes how to write the

Hi,I have a question about choosing some fairly basic security settings for an STM32H5.We are developing a system that uses both G4 and H5 micros. We have developed a largely common bootloader that receives a signed encrypted application over variously USB, UART, or CAN, and flashes it to internal memory. This is working on the G4 and H5.For the G4, we understand that if we select "Level 1" read protection, the bootloader will still be able to erase and re-flash a new application but a user will not be able to gain access to the code (bootloader, application, or data in CC RAM). Further, the G4 can be reverted to Level 0 if required, but this will erase the proprietary code.Ideally, we would like the same security behaviour on the H5. I have been reading about the bewildering selection of security settings with privileged and secure settings for individual peripherals but I feel this is more complicated than we require. Our bootloader already prevents some

Typical bootloaders (including some of ST's built-in bootloaders for other processors) typically allow a code image to be loaded into the processor via some kind of serial link (UART, SPI, CAN, etc), without needing an ST-Link or other debug hardware. These make bootloaders ideal for in-field upgrades of products.OEMiROT/OEMuROT has some features of a bootloader, in that a new image can be placed in a special area of flash and (if it passes all the various checks) then be executed.However, there is no way of actually putting that image in flash without an ST-Link or similar, since this is needed to unlock the chip via the DA process. So if you want to do an in-field upgrade of your product's firmware without any debug hardware, OEMiROT in its current form isn't the solution.Our approach is for our application to download the image into a reserved area of RAM and then switch to the bootloader, where our adapted version of OEMiROT copies this image from RAM to the

Hello Team,We have faced the Firmware ( hex file ) theft by Reverse engineering , Our competitor 2 Times. Yes, Two times , while RDP1 is set. We do not have contarct Manufacture in our whole process.Even Reading / Comparing intertlock of 96 bit UID failed.MCU is STM32F303.Can any one suggest a very high Strong Method which ensue complete guarantee for Firmware Protection from any threats. ?It seems STM32 is so famous that , its weak-leak point also Known.Getting Assembly / might be "C" code from Hex file looks Staright forward to crackers.

Hi, I'm building a medical device that will use an STM32 MCU and requires secure boot and secure firmware updates (over USB-C preferably). I have little experience with implementing secure bootloaders, and am looking for a solution that could allow me to get secure boot working out-of-the-box with minimal setup. I've seen that SBSFU offers example projects for secure boot on some MCUs, while MCUboot is also available for some others. It also looks like the STM32U5 series supports their own secure firmware updates based on AN4992. What's the difference between all of these solutions? Out of all the solutions ST offers for secure boot, which ones are the newest/recommended and easiest to get set up with? Because I'm looking for a low-cost MCU, I've identified the STM32L471, STM32L476, and STM32U575 as potential candidates that could support secure boot, but I'm lost as to how to actually set it up or what software solution to use. I'd love to hear anyone else's suggestions for other M

In STM32Cube_FW_H7RS_V1.3.0, file Projects/STM32H7S78-DK/Applications/ROT/OEMiROT_Boot/Inc/flash_layout.h:The macro OEMIROT_LOAD_AND_RUN has 3 possible settings, and we're using the NO_LOAD_AND_RUN to execute code (in external flash) in place.However, we're also using external RAM in our application, and this must be enabled in the bootloader, as the app attempts to initialise values in external RAM at startup.Unfortunately, the external RAM is only initialised if you select LOAD_AND_RUN_EXT_RAM.There is a workaround: in boot_hal.c and low_level_ext_ram.c, replace every instance (3 in each file) of:#if (OEMIROT_LOAD_AND_RUN == LOAD_AND_RUN_EXT_RAM)...with something like:

We are seeing a very odd data corruption issue which is highly repeatable, and appears to be related to a configuration setting which we haven't yet identified.In our system (running on an STM32H7S7), we're using the STiROT + OEMuROT secure bootloader to load our application. After a minute or two, the application causes a hard fault.The issue comes down to a POP instruction. I can see in the debugger that a value is being copied from the stack to a register, but one of the bits is flipped. Subsequent instructions do some indirection which ultimately causes the hard fault.It's always the same instruction in the same line of code. It always occurs within the first minute or two of execution.Using the debugger, we can see that the value in the stack (stored in DTCM) is correct. The error occurs when it's copied to the register. And although the error always occurs at the same address, it doesn't appear to be a fault with that location

Firmware Package: STM32Cube_FW_H5_V1.6.0 Product ProblemDA regression fails with timeout. I cannot recover the board. I was trying to run the STiROT Template example (STiROT_Appli) on the STM32H573I-DK board. 1. I ran a custom provisioning script (based on ob_flash_programming.sh + obkey_provisioning.sh)2. During image flashing step, I accidentally flashed an unsigned binary (appli.bin) instead of the signed image (appli_init_sign.hex)3. OBKey provisioning (DA_Config.obk, STiRoT_Config.obk, STiRoT_Data.obk) may have failed due to the MCU being in an unstable state4. I then set Product State to PROVISIONED (0x2E) Discovery output Discovery succeeds and shows- PSA lifecycle: ST_LIFECYCLE_IROT_PROVI

Hi everyone,I am trying to generate a professional SBOM for my project.I have a few questions regarding the best workflow:Tooling & Detection: What the best tool to generate the SBOM.I tried using ScanCode, but it didn't find any component in my project (e.g., FreeRTOS). I had to manually add .about files to the folder to get results. Is there a better tool that can generate the SBOM with minimal manual intervention?ST Cube SBOM : The Cube MCU packages contain dozens of libraries (FatFS, FreeRTOS, USB_Host, etc.). If my project only uses FatFS, the package JSON still lists everything. Do I have to manually extract the components I use from the ST JSON? how to get use of the ST SBOM?I’d love to hear if anyone has a script or a specific toolchain that automates this without the manual "copy-paste" from the ST manifests

In OEMiROT_Boot/Src/low_level_ext_flash.c, function Ext_Flash_EraseSector(),  a call is made to EXTMEM_MemoryMappedMode() immediately before the sector erase takes place, to temporarily disable memory-mapped mode for the external flash, with the function called again afterwards to re-enable it.As @ken5 reported previously, we found that these flash erases can cause corruption in the external RAM.After a lot of experimentation and head-scratching, we've found that if the external RAM is also removed from the memory map before a flash erase, and re-enabled afterwards, these corruption issues appears to go away (pendi

Hi ST team,I am using X-CUBE-SBSFU V2.8.0, project: Device: STM32H753Base example: NUCLEO-H753ZI 2_ImagesI ported UART pins/port for my H753 EVAL board.ProblemBuild fails in SECoreBin with GNU14.3 toolchain:C:/.../2_Images_SECoreBin/Src/se_crypto_bootloader.c:222:(.text.SE_CRYPTO_Decrypt_Init+0x16): dangerous relocation: unsupported relocation However , Then i shifted to 13.3 tool chain , then everything works fine for me.  Please confirm whether this is a known GCC 14.3 compatibility issue for SBSFU v2.8.0 key generation. If yes, could you share an official patch for prebuild.sh / key assembly generation so generated key symbols are fully compatible with newer GNU/binutils?

Hi everyone,We’ve been using the XCUBE-SBSFU bootloader in our industrial-grade project and recently noticed that SBSFU is now labeled as a legacy bootloader. It seems the new recommended bootloader is based on MCUBoot. Additionally, I’ve come across information on STiRoT, which implements a root of trust similar to what SBSFU legacy already offers.This has left us with a few questions, and we’d greatly appreciate any clarification:Why has SBSFU been marked as legacy and replaced? Were there specific limitations or issues with SBSFU that led to this change?How do we transition to MCUBoot? The MCUBoot website mentions it doesn’t currently support STM32 controllers, and the ST wiki says support is “coming soon.”What role does STiRoT play? It seems similar to SBSFU legacy but is relatively new. Is it a better option? Should we consider switching to it, and if so, why?Any insights or guidance would be greatly appreciated.

Hi Everyone,I'm following the: How to enable RDP-like product state flash protection in STM32H5 microcontrollersexample using an STM32H573xx devkit and an ST‑Link. I ended up bricking my devkit while attempting the regression step. My ST provisioning integrity status:0xf5f5f5f5I have another dev kit available for testing, but I haven't been able to find an H573xx example that uses the HAL code base. If anyone can point me to a HAL-based example for the STM32H573 series implementing JTAG protection. Many Thanks! 

Hi everyone,I am working on a custom board based on the STM32U575RGT6 (TrustZone enabled, FreeRTOS). I have successfully ported the SBSFU example originally provided for the B-U585I-IOT02A.My configuration is:MCUBOOT_APP_IMAGE_NUMBER = 1 (Single combined S and NS image)No external loader.To meet my application needs, I added a custom FLASH_STORAGE area at the end of the flash for EEPROM emulation. To do this cleanly, I modified flash_layout.h to dynamically compute the available FLASH_NS_PARTITION_SIZE based on the remaining space.The Problem: When I use MCUBOOT_OVERWRITE_ONLY, the OTA update (via Y-Modem) works perfectly. However, when I try to use the Swap mode (by commenting out #defi

Hi ST team,I am trying to develop a secure bootloader and firmware update solution for STM32H735 MCU. I was looking at ST's implementations, SBSFU legacy and SBSFU by MCUboot. Could you give me some guidance, which would be the better choice to start from and port to my chip? I saw that SBSFU by MCUboot is targeted only to STM32H7S, and not STM32H7, so I assume if I want to go with MCUBoot, most of the code built on top of MCUBoot by ST is not going to be usable for me, is that correct?I need these features for the bootloader:immutable bootloader implementationapplication authentication (using signature verification)secure application upd

Hello, I'm looking for some advice on how to progress, beginning from a fairly novice position, with a secure bootloader.  I'm beginning a project where at least a secure update process (where the existing application does the update) is desired.  Ideally I'd have an encrypted and signed application updates being delivered to my target application and put that away in flash, then reset the MCU and have a bootloader validate / process the update. I've found Zephyr and had a small play with the MCUBoot -- its seem pretty cool,  though I also found that some combinations of options created interesting build failures that were confusing.  I've just stumbled across the SBSFU project - which appears to utilise some of MCUBoot, but I'm having a slow time making sense of it, with its half a dozens projects and plethora of source files.  If there is not a STM project that can be configured and directly used on the U575 -- I'm hoping there is at l

I see only one other answer to this question, here: Solved: TrustZone Enable afterwards - STMicroelectronics CommunityHowever, others are not answered. Can you confirm that there is a solid reason why the TrustZone cannot be enabled after the project has been created? Does it scramble to ioc file? Was this an issue with previous versions of CubeMX and perhaps no longer an issue? Core: M33

Our own non-secure application is based on "SMAK_Appli" in the STM32TRUSTEE-SM example and in principle, it works, but debugging is giving me issues. This is with STM32CubeIDE latest version and all tools software and firmware updated to their latest versions, too.Issue 1: Using STLINK-V3 to start debugging, whenever there has been a code change, the first attempt results in a verification error (see log below) and the second attempt then works. This is 100% consistent and terribly annoying since starting the non-secure debugging session is very slow to begin with.Issue 2: Using J-Link to start debugging, it claims flash was programmed (very fast) and debugging seems to work at first, but I found that flash programming was not effective. The flash content is always what it was programmed with using STLINK. So if I want to use J-Link, I have to program with STLINK (twice), then switch to J-Link but I cannot successfully program changed flash content with J-Link.A