BRLY-LOGOFAIL-2023-025

Memory contents leak / information disclosure vulnerability in DXE driver.

Public Disclosure Date: Jun 19, 2024

CVE ID

CVE-2023-5058

Vendors Affected

LogoFAIL

Products Affected

SystemImageDecoderDxe

Summary

BINARLY efiXplorer team has discovered a memory contents leak / information disclosure vulnerability. Lack of synchronization between PaletteSize calculated from BitsPerPixel in BMP Image Header and PaletteIndex calculated from data in BMP Image allows OOB Read in Phoenix firmware.

Potential Impact

An attacker with local privileged access can exploit this vulnerability to read the contents of the physical memory and use this information to exploit other vulnerabilities in DXE. A malicious code installed as a result of the vulnerability exploitation in a DXE driver could survive across an operating system (OS) boot process and runtime or modify NVRAM area on SPI flash storage (to gain persistence on target platform). Additionally, this vulnerability potentially could be used by threat actors to bypass OS security mechanisms (modify privileged memory or runtime variables), influence on the OS boot process, and in some cases would allow an attacker to hook or modify EFI Runtime services.

Vulnerability Information

BINARLY internal vulnerability identifier: BRLY-LOGOFAIL-2023-025
Phoenix PSIRT assigned CVE identifier: CVE-2023-5058
CVSS v3.1: 3.2 Low AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:N

Table of Contents

01.Affected modules

02.Vulnerability description

03.Disclosure timeline

04.Acknowledgements

Affected modules

Module name	Module GUID	Module SHA256
SystemImageDecoderDxe	5F65D21A-8867-45D3-A41A-526F9FE2C598	86E6C85A8FF7C1DB8FF7292521223C546DD4F40F5168F7DA3134916BF52DA81D

Vulnerability description

The pseudocode of the vulnerable function is shown below:

// local variable allocation has failed, the output may be wrong!
EFI_STATUS __fastcall DbDecodeImage(BUFFER_INDICATOR *Bi, EFI_IMAGE_INPUT *ImageInput)
{
  UINTN BufferSize; // rcx
  BMP_COLOR_PALETTE *Palette; // r15
  EFI_STATUS Status; // rsi
  void *Start; // rax
  void *Current; // rcx
  char *Start_plus_BMP_FILE_HEADER; // rax
  char *Start_plus_BufferSize; // rcx
  size_t ImageSize; // rdi
  __int64 BmpHeaderSize; // r12
  __int64 ColorAmount; // r14
  EFI_GRAPHICS_OUTPUT_BLT_PIXEL *mem; // rax
  UINT16 BitsPerPixel; // cx
  size_t PaletteSize; // r14 MAPDST
  void *Start_plus_BmpHeaderSize; // rax
  void *Start_plus_BufferSize_1; // rcx
  void *ImageBuffer; // rax MAPDST
  void *Start_plus_ImageOffset; // rcx
  UINT32 Height; // er8
  int i; // ebx
  EFI_GRAPHICS_OUTPUT_BLT_PIXEL *PixelPtr; // rdi
  __int64 ImageIndex; // r9
  UINT32 Width; // er11
  UINT32 j; // er10
  unsigned __int64 offset; // rcx
  EFI_GRAPHICS_OUTPUT_BLT_PIXEL v29; // eax
  UINT8 v30; // al
  __int64 index; // rcx
  __int64 v32; // rcx
  unsigned __int64 v33; // rcx
  __int64 v34; // rax
  unsigned __int64 v35; // rcx
  __int64 BitIndex; // r12
  unsigned __int64 PaletteIndex; // rdx
  __int64 v38; // rax
  int v39; // eax
  BMP_FILE_HEADER Bfh; // [rsp+20h] [rbp-40h]
  BMP_INFO_HEADER Bih; // [rsp+30h] [rbp-30h]
  UINT64 ScratchedBufferSize; // [rsp+A0h] [rbp+40h] OVERLAPPED
  EFI_GRAPHICS_OUTPUT_BLT_PIXEL Color; // [rsp+A0h] [rbp+40h] FORCED

  BufferSize = Bi->BufferSize;
  Bfh.ImageOffset = 0;
  Palette = 0i64;
  Bih.BitsPerPixel = 0;
  Status = 0i64;
  Bih.ImageSize = 0;
  *(_QWORD *)&Bih.HeaderSize = 0i64;
  Bih.Height = 0;
  if ( BufferSize <= 0x36 )
    return Status;
  Start = Bi->Start;
  Bi->Current = Bi->Start;
  ScratchedBufferSize = sizeof(BMP_FILE_HEADER);
  if ( (char *)Start + sizeof(BMP_FILE_HEADER) > (char *)Start + BufferSize )
    return Status;
  if ( BiReadBuffer(Bi, &Bfh, &ScratchedBufferSize, (char *)Start + sizeof(BMP_FILE_HEADER)) )
    return Status;
  Current = Bi->Start;
  ScratchedBufferSize = sizeof(BMP_INFO_HEADER);
  Start_plus_BMP_FILE_HEADER = (char *)Current + sizeof(BMP_FILE_HEADER);
  Start_plus_BufferSize = (char *)Current + Bi->BufferSize;
  Bi->Current = Start_plus_BMP_FILE_HEADER;
  if ( Start_plus_BMP_FILE_HEADER + sizeof(BMP_INFO_HEADER) > Start_plus_BufferSize
    || BiReadBuffer(Bi, &Bih, &ScratchedBufferSize, Start_plus_BMP_FILE_HEADER + sizeof(BMP_INFO_HEADER))
    || Bfh.BmpId[0] != 'B'
    || Bfh.BmpId[1] != 'M' )
  {
    return Status;
  }
  ImageSize = Bih.ImageSize;
  BmpHeaderSize = Bih.HeaderSize + sizeof(BMP_FILE_HEADER);
  ColorAmount = 1 << SLOBYTE(Bih.BitsPerPixel);
  ScratchedBufferSize = Bih.ImageSize;
  mem = (EFI_GRAPHICS_OUTPUT_BLT_PIXEL *)malloc(4i64 * Bih.Height * Bih.Width);
  ImageInput->Bitmap = mem;
  if ( !mem )
    return EFI_OUT_OF_RESOURCES;
  BitsPerPixel = Bih.BitsPerPixel;
  ImageInput->Height = Bih.Height;
  ImageInput->Width = Bih.Width;
  if ( !ImageSize )
  {
    ImageSize = Bih.Height * ((((BitsPerPixel * (unsigned __int64)Bih.Width) >> 3) + 3) & 0xFFFFFFFC);
    ScratchedBufferSize = Bih.Height * ((((BitsPerPixel * (unsigned __int64)Bih.Width) >> 3) + 3) & 0xFFFFFFFC);
  }
  if ( (unsigned __int16)(BitsPerPixel - 1) <= 7u )
  {
    PaletteSize = 4 * ColorAmount;
    Palette = (BMP_COLOR_PALETTE *)malloc(PaletteSize);// Root cause #2: OOB index. Lack of synchronization between PaletteSize and PaletteIndex.
    if ( !Palette )
      return EFI_OUT_OF_RESOURCES;
    Start_plus_BmpHeaderSize = (char *)Bi->Start + BmpHeaderSize;
    Start_plus_BufferSize_1 = (char *)Bi->Start + Bi->BufferSize;
    Bi->Current = Start_plus_BmpHeaderSize;
    if ( (char *)Start_plus_BmpHeaderSize + PaletteSize <= Start_plus_BufferSize_1 )
      BiReadBuffer(Bi, Palette, &PaletteSize, (char *)Start_plus_BmpHeaderSize + PaletteSize);
  }
  ImageBuffer = malloc(ImageSize);
  if ( ImageBuffer )
  {
    Start_plus_ImageOffset = (char *)Bi->Start + Bfh.ImageOffset;
    Bi->Current = Start_plus_ImageOffset;
    if ( (void *)((unsigned __int64)Start_plus_ImageOffset + ImageSize) <= (char *)Bi->Start + Bi->BufferSize )
      BiReadBuffer(Bi, ImageBuffer, &ScratchedBufferSize, (char *)Start_plus_ImageOffset + ImageSize);
    Height = Bih.Height;
    i = 0;
    PixelPtr = ImageInput->Bitmap;
    ImageIndex = 0i64;
    Color.Reserved = 0;
    if ( !Bih.Height )
      goto exit;
    Width = Bih.Width;
    while ( 1 )
    {
      j = 0;
      if ( Width )
        break;
LABEL_40:
      if ( ImageIndex & 3 )
        v39 = 4 - (ImageIndex & 3);
      else
        v39 = 0;
      ImageIndex = (unsigned int)(v39 + ImageIndex);
      if ( ++i >= Height )
        goto exit;
    }
    while ( 1 )
    {
      if ( Bih.BitsPerPixel == 1 )              // 2 Color Mode
                                                // CRASH area
      {
        BitIndex = 7i64;
        while ( j < Width )
        {
          PaletteIndex = ((unsigned __int64)*((unsigned __int8 *)ImageBuffer + ImageIndex) >> BitIndex) & 1;// OOB read Root Cause #3
          *(_WORD *)&Color.Green = *(_WORD *)&Palette[PaletteIndex].Green;// OOB read Root Cause #2
                                                // ^ Both Red + Green in Color and Palette objects
          Color.Blue = Palette[PaletteIndex].Blue;// OOB read Root Cause #2
          v38 = j++;
          --BitIndex;
          PixelPtr[v38 + Width * (Height - i - 1)] = Color;
          Height = Bih.Height;
          Width = Bih.Width;
        }
        --j;
        ImageIndex = (unsigned int)(ImageIndex + 1);
        goto LABEL_39;
      }
      if ( Bih.BitsPerPixel == 4 )              // 16 Color Mode
        break;
      switch ( Bih.BitsPerPixel )
      {
        case 8u:                                // 256 Color Mode
                                                // CRASH case x2
          v32 = *((unsigned __int8 *)ImageBuffer + ImageIndex);
          ImageIndex = (unsigned int)(ImageIndex + 1);
          *(_WORD *)&Color.Green = *(_WORD *)&Palette[v32].Green;// OOB read Root Cause #2
                                                // ^ Both Red + Green in Color and Palette objects
          v30 = Palette[v32].Blue;              // OOB read Root Cause #2
LABEL_30:
          index = Width * (Height - i - 1);
LABEL_33:
          Color.Blue = v30;
          offset = j + index;
          v29 = Color;
          goto LABEL_34;
        case 0x18u:                             // 16M Color Mode
          *(_WORD *)&Color.Green = *(_WORD *)((char *)ImageBuffer + ImageIndex + 1);
          v30 = *((_BYTE *)ImageBuffer + ImageIndex);
          ImageIndex = (unsigned int)(ImageIndex + 3);
          goto LABEL_30;
        case 0x20u:
          offset = j + (unsigned __int64)(Width * (Height - i - 1));
          v29 = *(EFI_GRAPHICS_OUTPUT_BLT_PIXEL *)((char *)ImageBuffer + ImageIndex);
          ImageIndex = (unsigned int)(ImageIndex + 4);
LABEL_34:
          PixelPtr[offset] = v29;
          Height = Bih.Height;
          Width = Bih.Width;
          break;
      }
LABEL_39:
      if ( ++j >= Width )
        goto LABEL_40;
    }
    v33 = (unsigned __int64)*((unsigned __int8 *)ImageBuffer + ImageIndex) >> 4;
    *(_WORD *)&Color.Green = *(_WORD *)&Palette[v33].Green;// OOB read Root Cause #2
                                                // ^ Both Red + Green in Color and Palette objects
    Color.Blue = Palette[v33].Blue;             // OOB read Root Cause #2
    v34 = j++;
    PixelPtr[v34 + Width * (Height - i - 1)] = Color;
    LOBYTE(v33) = *((_BYTE *)ImageBuffer + ImageIndex);
    ImageIndex = (unsigned int)(ImageIndex + 1);
    v35 = v33 & 0xF;
    *(_WORD *)&Color.Green = *(_WORD *)&Palette[v35].Green;
    v30 = Palette[v35].Blue;
    index = Bih.Width * (Bih.Height - i - 1);
    goto LABEL_33;
  }
  Status = EFI_OUT_OF_RESOURCES;
exit:
  if ( Palette )
    gEfiBootServices->FreePool(Palette);
  if ( ImageBuffer )
    gEfiBootServices->FreePool(ImageBuffer);
  return Status;
}

As we can see from the pseudocode, PaletteSize and PaletteIndex are calculated is independently from each other, which leads to OOB read cases.

Disclosure timeline

This bug is subject to a 90 day disclosure deadline. After 90 days elapsed or a patch has been made broadly available (whichever is earlier), the bug report will become visible to the public.

Disclosure Activity	Date (YYYY-mm-dd)
Lenovo PSIRT is notified	2023-06-21
Lenovo ID (LEN-132940) is assigned	2023-06-22
CERT/CC is notified	2023-07-10
Phoenix PSIRT confirmed reported issues	2023-09-10
Phoenix PSIRT assigned CVE ID	2023-11-27
Phoenix advisory release date	2023-12-06
BINARLY public disclosure date	2024-06-19

Acknowledgements

BINARLY efiXplorer team

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Potential Impact

Module name

Module GUID

Module SHA256

SystemImageDecoderDxe

5F65D21A-8867-45D3-A41A-526F9FE2C598

86E6C85A8FF7C1DB8FF7292521223C546DD4F40F5168F7DA3134916BF52DA81D

// local variable allocation has failed, the output may be wrong! EFI_STATUS __fastcall DbDecodeImage(BUFFER_INDICATOR *Bi, EFI_IMAGE_INPUT *ImageInput) { UINTN BufferSize; // rcx BMP_COLOR_PALETTE *Palette; // r15 EFI_STATUS Status; // rsi void *Start; // rax void *Current; // rcx char *Start_plus_BMP_FILE_HEADER; // rax char *Start_plus_BufferSize; // rcx size_t ImageSize; // rdi __int64 BmpHeaderSize; // r12 __int64 ColorAmount; // r14 EFI_GRAPHICS_OUTPUT_BLT_PIXEL *mem; // rax UINT16 BitsPerPixel; // cx size_t PaletteSize; // r14 MAPDST void *Start_plus_BmpHeaderSize; // rax void *Start_plus_BufferSize_1; // rcx void *ImageBuffer; // rax MAPDST void *Start_plus_ImageOffset; // rcx UINT32 Height; // er8 int i; // ebx EFI_GRAPHICS_OUTPUT_BLT_PIXEL *PixelPtr; // rdi __int64 ImageIndex; // r9 UINT32 Width; // er11 UINT32 j; // er10 unsigned __int64 offset; // rcx EFI_GRAPHICS_OUTPUT_BLT_PIXEL v29; // eax UINT8 v30; // al __int64 index; // rcx __int64 v32; // rcx unsigned __int64 v33; // rcx __int64 v34; // rax unsigned __int64 v35; // rcx __int64 BitIndex; // r12 unsigned __int64 PaletteIndex; // rdx __int64 v38; // rax int v39; // eax BMP_FILE_HEADER Bfh; // [rsp+20h] [rbp-40h] BMP_INFO_HEADER Bih; // [rsp+30h] [rbp-30h] UINT64 ScratchedBufferSize; // [rsp+A0h] [rbp+40h] OVERLAPPED EFI_GRAPHICS_OUTPUT_BLT_PIXEL Color; // [rsp+A0h] [rbp+40h] FORCED BufferSize = Bi->BufferSize; Bfh.ImageOffset = 0; Palette = 0i64; Bih.BitsPerPixel = 0; Status = 0i64; Bih.ImageSize = 0; *(_QWORD *)&Bih.HeaderSize = 0i64; Bih.Height = 0; if ( BufferSize <= 0x36 ) return Status; Start = Bi->Start; Bi->Current = Bi->Start; ScratchedBufferSize = sizeof(BMP_FILE_HEADER); if ( (char *)Start + sizeof(BMP_FILE_HEADER) > (char *)Start + BufferSize ) return Status; if ( BiReadBuffer(Bi, &Bfh, &ScratchedBufferSize, (char *)Start + sizeof(BMP_FILE_HEADER)) ) return Status; Current = Bi->Start; ScratchedBufferSize = sizeof(BMP_INFO_HEADER); Start_plus_BMP_FILE_HEADER = (char *)Current + sizeof(BMP_FILE_HEADER); Start_plus_BufferSize = (char *)Current + Bi->BufferSize; Bi->Current = Start_plus_BMP_FILE_HEADER; if ( Start_plus_BMP_FILE_HEADER + sizeof(BMP_INFO_HEADER) > Start_plus_BufferSize || BiReadBuffer(Bi, &Bih, &ScratchedBufferSize, Start_plus_BMP_FILE_HEADER + sizeof(BMP_INFO_HEADER)) || Bfh.BmpId[0] != 'B' || Bfh.BmpId[1] != 'M' ) { return Status; } ImageSize = Bih.ImageSize; BmpHeaderSize = Bih.HeaderSize + sizeof(BMP_FILE_HEADER); ColorAmount = 1 << SLOBYTE(Bih.BitsPerPixel); ScratchedBufferSize = Bih.ImageSize; mem = (EFI_GRAPHICS_OUTPUT_BLT_PIXEL *)malloc(4i64 * Bih.Height * Bih.Width); ImageInput->Bitmap = mem; if ( !mem ) return EFI_OUT_OF_RESOURCES; BitsPerPixel = Bih.BitsPerPixel; ImageInput->Height = Bih.Height; ImageInput->Width = Bih.Width; if ( !ImageSize ) { ImageSize = Bih.Height * ((((BitsPerPixel * (unsigned __int64)Bih.Width) >> 3) + 3) & 0xFFFFFFFC); ScratchedBufferSize = Bih.Height * ((((BitsPerPixel * (unsigned __int64)Bih.Width) >> 3) + 3) & 0xFFFFFFFC); } if ( (unsigned __int16)(BitsPerPixel - 1) <= 7u ) { PaletteSize = 4 * ColorAmount; Palette = (BMP_COLOR_PALETTE *)malloc(PaletteSize);// Root cause #2: OOB index. Lack of synchronization between PaletteSize and PaletteIndex. if ( !Palette ) return EFI_OUT_OF_RESOURCES; Start_plus_BmpHeaderSize = (char *)Bi->Start + BmpHeaderSize; Start_plus_BufferSize_1 = (char *)Bi->Start + Bi->BufferSize; Bi->Current = Start_plus_BmpHeaderSize; if ( (char *)Start_plus_BmpHeaderSize + PaletteSize <= Start_plus_BufferSize_1 ) BiReadBuffer(Bi, Palette, &PaletteSize, (char *)Start_plus_BmpHeaderSize + PaletteSize); } ImageBuffer = malloc(ImageSize); if ( ImageBuffer ) { Start_plus_ImageOffset = (char *)Bi->Start + Bfh.ImageOffset; Bi->Current = Start_plus_ImageOffset; if ( (void *)((unsigned __int64)Start_plus_ImageOffset + ImageSize) <= (char *)Bi->Start + Bi->BufferSize ) BiReadBuffer(Bi, ImageBuffer, &ScratchedBufferSize, (char *)Start_plus_ImageOffset + ImageSize); Height = Bih.Height; i = 0; PixelPtr = ImageInput->Bitmap; ImageIndex = 0i64; Color.Reserved = 0; if ( !Bih.Height ) goto exit; Width = Bih.Width; while ( 1 ) { j = 0; if ( Width ) break; LABEL_40: if ( ImageIndex & 3 ) v39 = 4 - (ImageIndex & 3); else v39 = 0; ImageIndex = (unsigned int)(v39 + ImageIndex); if ( ++i >= Height ) goto exit; } while ( 1 ) { if ( Bih.BitsPerPixel == 1 ) // 2 Color Mode // CRASH area { BitIndex = 7i64; while ( j < Width ) { PaletteIndex = ((unsigned __int64)*((unsigned __int8 *)ImageBuffer + ImageIndex) >> BitIndex) & 1;// OOB read Root Cause #3 *(_WORD *)&Color.Green = *(_WORD *)&Palette[PaletteIndex].Green;// OOB read Root Cause #2 // ^ Both Red + Green in Color and Palette objects Color.Blue = Palette[PaletteIndex].Blue;// OOB read Root Cause #2 v38 = j++; --BitIndex; PixelPtr[v38 + Width * (Height - i - 1)] = Color; Height = Bih.Height; Width = Bih.Width; } --j; ImageIndex = (unsigned int)(ImageIndex + 1); goto LABEL_39; } if ( Bih.BitsPerPixel == 4 ) // 16 Color Mode break; switch ( Bih.BitsPerPixel ) { case 8u: // 256 Color Mode // CRASH case x2 v32 = *((unsigned __int8 *)ImageBuffer + ImageIndex); ImageIndex = (unsigned int)(ImageIndex + 1); *(_WORD *)&Color.Green = *(_WORD *)&Palette[v32].Green;// OOB read Root Cause #2 // ^ Both Red + Green in Color and Palette objects v30 = Palette[v32].Blue; // OOB read Root Cause #2 LABEL_30: index = Width * (Height - i - 1); LABEL_33: Color.Blue = v30; offset = j + index; v29 = Color; goto LABEL_34; case 0x18u: // 16M Color Mode *(_WORD *)&Color.Green = *(_WORD *)((char *)ImageBuffer + ImageIndex + 1); v30 = *((_BYTE *)ImageBuffer + ImageIndex); ImageIndex = (unsigned int)(ImageIndex + 3); goto LABEL_30; case 0x20u: offset = j + (unsigned __int64)(Width * (Height - i - 1)); v29 = *(EFI_GRAPHICS_OUTPUT_BLT_PIXEL *)((char *)ImageBuffer + ImageIndex); ImageIndex = (unsigned int)(ImageIndex + 4); LABEL_34: PixelPtr[offset] = v29; Height = Bih.Height; Width = Bih.Width; break; } LABEL_39: if ( ++j >= Width ) goto LABEL_40; } v33 = (unsigned __int64)*((unsigned __int8 *)ImageBuffer + ImageIndex) >> 4; *(_WORD *)&Color.Green = *(_WORD *)&Palette[v33].Green;// OOB read Root Cause #2 // ^ Both Red + Green in Color and Palette objects Color.Blue = Palette[v33].Blue; // OOB read Root Cause #2 v34 = j++; PixelPtr[v34 + Width * (Height - i - 1)] = Color; LOBYTE(v33) = *((_BYTE *)ImageBuffer + ImageIndex); ImageIndex = (unsigned int)(ImageIndex + 1); v35 = v33 & 0xF; *(_WORD *)&Color.Green = *(_WORD *)&Palette[v35].Green; v30 = Palette[v35].Blue; index = Bih.Width * (Bih.Height - i - 1); goto LABEL_33; } Status = EFI_OUT_OF_RESOURCES; exit: if ( Palette ) gEfiBootServices->FreePool(Palette); if ( ImageBuffer ) gEfiBootServices->FreePool(ImageBuffer); return Status; }

Disclosure Activity

Date (YYYY-mm-dd)

Lenovo PSIRT is notified

2023-06-21

Lenovo ID (LEN-132940) is assigned

2023-06-22

CERT/CC is notified

2023-07-10

Phoenix PSIRT confirmed reported issues

2023-09-10

Phoenix PSIRT assigned CVE ID

2023-11-27

Phoenix advisory release date

2023-12-06

BINARLY public disclosure date

2024-06-19

Potential Impact

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Vulnerability Information

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Affected modules

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Vulnerability description

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Disclosure timeline

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Acknowledgements

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Potential Impact

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Vulnerability Information

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Affected modules

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Vulnerability description

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Disclosure timeline

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Acknowledgements

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See if you are impacted now with our Firmware Vulnerability Scanner