CVE-2026-21353: DNG SDK Integer Overflow RCE Vulnerability

CVE-2026-21353 Overview

CVE-2026-21353 is an Integer Overflow or Wraparound vulnerability (CWE-190) affecting Adobe DNG SDK versions 1.7.1 2410 and earlier. This vulnerability could result in arbitrary code execution in the context of the current user when processing specially crafted DNG (Digital Negative) files. Exploitation requires user interaction, specifically that a victim must open a malicious file.

Critical Impact

Successful exploitation allows attackers to execute arbitrary code with the privileges of the current user, potentially leading to complete system compromise, data theft, or malware installation through malicious image files.

Affected Products

• Adobe DNG SDK version 1.7.1 2410
• Adobe DNG SDK versions earlier than 1.7.1 2410
• Applications integrating vulnerable DNG SDK versions

Discovery Timeline

• 2026-02-10 - CVE-2026-21353 published to NVD
• 2026-02-10 - Last updated in NVD database

Technical Details for CVE-2026-21353

Vulnerability Analysis

This vulnerability stems from improper handling of integer arithmetic operations within the DNG SDK's image processing routines. When parsing DNG file metadata or pixel data, the SDK performs calculations that can result in integer overflow conditions. If an attacker crafts a DNG file with carefully chosen dimension or size values, the multiplication or addition operations can wrap around, resulting in a smaller-than-expected memory allocation.

The local attack vector requires the victim to open a malicious DNG file, which could be delivered through phishing emails, malicious websites, or file-sharing platforms. Since DNG is a common raw image format used by photographers and integrated into various image processing applications, the attack surface includes any software that leverages the Adobe DNG SDK for image parsing.

Root Cause

The root cause is an Integer Overflow or Wraparound condition (CWE-190) in the DNG SDK's memory allocation logic. When processing image dimensions or buffer sizes from untrusted input, the code performs arithmetic operations without adequate bounds checking. This allows integer values to exceed their maximum representable value and wrap around to a small positive number, leading to undersized buffer allocations.

Attack Vector

The attack requires local access and user interaction. An attacker must craft a malicious DNG file containing specially constructed values that trigger the integer overflow condition. When a victim opens this file using an application that relies on the vulnerable DNG SDK, the overflow occurs during parsing, leading to a heap-based buffer overflow when the undersized buffer is subsequently filled with image data. This memory corruption can be leveraged to achieve arbitrary code execution.

The exploitation chain typically involves:

1. Crafting a DNG file with malicious dimension or size values
2. Delivering the file to the victim through social engineering
3. Victim opening the file with a vulnerable application
4. Integer overflow triggering undersized memory allocation
5. Subsequent write operations corrupting heap memory
6. Attacker achieving code execution through memory corruption techniques

Detection Methods for CVE-2026-21353

Indicators of Compromise

• Unusual DNG files with abnormally large or suspicious dimension values in metadata
• Crash logs or error reports from applications processing DNG files indicating memory corruption
• Unexpected child processes spawned from image processing applications
• Memory access violations originating from DNG SDK library components

Detection Strategies

• Deploy endpoint detection to monitor for applications processing DNG files exhibiting anomalous behavior
• Implement file inspection rules to detect DNG files with suspicious or malformed metadata headers
• Monitor for heap corruption or buffer overflow signatures in applications using the DNG SDK
• Enable crash dump analysis to identify exploitation attempts through memory corruption patterns

Monitoring Recommendations

• Enable verbose logging for applications that process DNG files in high-risk environments
• Configure SentinelOne agents to detect and alert on suspicious code execution patterns from image processing applications
• Monitor file download activity for DNG files from untrusted sources
• Implement application whitelisting to restrict which applications can process DNG files

How to Mitigate CVE-2026-21353

Immediate Actions Required

• Update Adobe DNG SDK to the latest patched version as specified in Adobe Security Bulletin APSB26-23
• Audit all applications in your environment that may use the DNG SDK and prioritize updates
• Implement user awareness training to avoid opening DNG files from untrusted sources
• Deploy endpoint protection to detect and block exploitation attempts

Patch Information

Adobe has released a security update addressing this vulnerability. Organizations should review the Adobe Security Bulletin APSB26-23 for detailed patch information and update to the latest version of the DNG SDK. Applications built on the DNG SDK should be recompiled with the patched library version.

Workarounds

• Restrict handling of DNG files to trusted sources only until patches can be applied
• Implement application-level controls to sandbox DNG file processing in isolated environments
• Deploy network-level controls to scan incoming DNG files for malformed or suspicious metadata
• Consider temporarily disabling DNG file processing capabilities in non-critical applications until updates are deployed

Organizations unable to immediately patch should prioritize network segmentation and enhanced monitoring of systems that process DNG files to detect potential exploitation attempts.