CVE-2026-24808: RawTherapee Buffer Overflow Vulnerability

CVE-2026-24808 Overview

CVE-2026-24808 is an Integer Overflow or Wraparound vulnerability discovered in RawTherapee, specifically affecting the rtengine modules. The vulnerability is associated with the program file dcraw.cc, a critical component used for raw image processing. This integer overflow condition could allow attackers to cause unexpected behavior, including potential memory corruption, denial of service, or arbitrary code execution when processing specially crafted image files.

Critical Impact

Successful exploitation of this integer overflow vulnerability could lead to memory corruption, application crashes, or potentially allow an attacker to execute arbitrary code on affected systems when processing malicious raw image files.

Affected Products

• RawTherapee through version 5.11
• RawTherapee rtengine modules (dcraw.cc)
• Systems processing untrusted raw image files with affected RawTherapee versions

Discovery Timeline

• 2026-01-27 - CVE CVE-2026-24808 published to NVD
• 2026-01-27 - Last updated in NVD database

Technical Details for CVE-2026-24808

Vulnerability Analysis

This vulnerability stems from an integer overflow or wraparound condition (CWE-190) in the RawTherapee image processing software. The flaw exists within the dcraw.cc file, which is part of the rtengine modules responsible for decoding and processing raw camera image formats. Integer overflow vulnerabilities occur when arithmetic operations produce results that exceed the maximum value that can be stored in the allocated integer type, causing the value to wrap around to a smaller number.

In the context of image processing software like RawTherapee, integer overflows are particularly dangerous because they can lead to undersized buffer allocations. When the software subsequently attempts to process image data using these incorrect buffer sizes, it can result in heap-based buffer overflows, out-of-bounds memory access, or other memory corruption issues.

The vulnerability requires local access and user interaction to exploit, meaning an attacker would need to convince a user to open a malicious raw image file with RawTherapee.

Root Cause

The root cause of CVE-2026-24808 is improper handling of integer arithmetic operations in the dcraw.cc file within RawTherapee's rtengine modules. When processing certain image metadata or dimension values, the software fails to validate that arithmetic operations on these values won't exceed integer boundaries. This can occur when calculating buffer sizes, image dimensions, or memory allocation requirements based on user-controlled data from raw image files.

Attack Vector

The attack vector for this vulnerability is local, requiring user interaction. An attacker would need to craft a malicious raw image file containing specially constructed values designed to trigger the integer overflow condition. The attack scenario typically involves:

1. The attacker creates a malicious raw image file with crafted metadata values
2. The victim downloads or receives the malicious file
3. The victim opens the file with RawTherapee version 5.11 or earlier
4. During image processing, the integer overflow is triggered in dcraw.cc
5. The overflow leads to memory corruption or other exploitable conditions

The vulnerability is triggered when the rtengine modules process the malicious image data, causing integer calculations to overflow and potentially leading to heap corruption or arbitrary code execution.

Detection Methods for CVE-2026-24808

Indicators of Compromise

• Unexpected RawTherapee application crashes when opening specific raw image files
• Memory corruption errors or segmentation faults in RawTherapee processes
• Unusual memory consumption patterns when processing raw images
• Application logs showing errors related to dcraw.cc or rtengine modules

Detection Strategies

• Monitor for RawTherapee application crashes, particularly those occurring during file open operations
• Implement file integrity monitoring on systems where RawTherapee processes untrusted image files
• Deploy endpoint detection rules that identify suspicious memory access patterns in image processing applications
• Use application sandboxing to contain potential exploitation attempts

Monitoring Recommendations

• Enable crash dump collection for RawTherapee to identify potential exploitation attempts
• Monitor system event logs for application faults related to RawTherapee executables
• Implement network monitoring to detect downloads of suspicious raw image file formats
• Review file access patterns for unusual raw image files being processed

How to Mitigate CVE-2026-24808

Immediate Actions Required

• Update RawTherapee to the latest version that includes the security fix
• Avoid processing raw image files from untrusted sources until patched
• Implement application sandboxing for RawTherapee to limit impact of potential exploitation
• Review and restrict file system permissions for directories containing raw image files

Patch Information

The fix for this vulnerability is addressed in GitHub Pull Request #7359. Users should update to a version of RawTherapee that includes this fix. The patch addresses the integer overflow condition in the dcraw.cc file by implementing proper bounds checking on arithmetic operations.

To verify you have a patched version:

1. Check your RawTherapee version (Help > About)
2. Ensure you are running a version newer than 5.11 that includes the security fix
3. Monitor the official RawTherapee release notes for security updates

Workarounds

• Do not open raw image files from untrusted or unknown sources with affected RawTherapee versions
• Run RawTherapee in a sandboxed environment or virtual machine when processing untrusted files
• Implement strict access controls to limit which users can process raw images
• Consider using alternative image processing software until a patch can be applied

# Configuration example
# Verify RawTherapee version and check for updates
rawtherapee --version

# Run RawTherapee with limited permissions (Linux example)
firejail --private rawtherapee

# Monitor for crashes related to RawTherapee
journalctl -f | grep -i rawtherapee