CVE-2026-21505 Overview
CVE-2026-21505 is an Input Validation Error vulnerability affecting iccDEV, a set of libraries and tools developed by the International Color Consortium (ICC) for the interaction, manipulation, and application of ICC color management profiles. Prior to version 2.3.1.2, iccDEV exhibits undefined behavior due to an invalid enum value, which can be exploited to cause application crashes and denial of service conditions.
Critical Impact
This vulnerability can lead to undefined behavior and application crashes when processing malformed ICC profile data, potentially causing denial of service in applications that rely on iccDEV for color management operations.
Affected Products
- iccDEV versions prior to 2.3.1.2
- Applications utilizing iccDEV libraries for ICC profile processing
- Systems processing untrusted ICC color management profiles
Discovery Timeline
- 2026-01-07 - CVE CVE-2026-21505 published to NVD
- 2026-01-08 - Last updated in NVD database
Technical Details for CVE-2026-21505
Vulnerability Analysis
The vulnerability resides in the icProfileHeader.h header file within the IccProfLib component. The root issue stems from the icMaterialColorSignature enum type definition, which lacked proper bounds and type specification. When the library processes ICC profile data containing values outside the expected enum range, the C/C++ standard does not define the resulting behavior, leading to undefined behavior conditions.
This undefined behavior is particularly dangerous because it can manifest differently across compilers, optimization levels, and platforms. In practical terms, an attacker can craft a malicious ICC profile that triggers this condition when processed by applications using vulnerable versions of iccDEV.
Root Cause
The vulnerability is classified under CWE-20 (Improper Input Validation). The icMaterialColorSignature enum was defined without explicit underlying type specification and lacked sentinel values to help sanitization tools detect out-of-range values. When ICC profile data contained material color signature values not explicitly enumerated, the compiler's assumptions about valid enum ranges could be violated, resulting in undefined behavior.
Attack Vector
The attack requires local access with user interaction, as an attacker must convince a user to open or process a maliciously crafted ICC profile file. The attack flow involves:
- Attacker creates a malformed ICC profile with an invalid material color signature value
- Victim application uses iccDEV library to process the malicious profile
- The invalid enum value triggers undefined behavior
- Application crashes or exhibits unpredictable behavior, resulting in denial of service
The following patch demonstrates the fix implemented in version 2.3.1.2:
} icColorSpaceSignature;
-typedef enum {
+typedef enum : icUInt32Number {
icSigNoMCSData = 0x00000000,
icSigMCSData = 0x6d630000, /* "mc0000" */
- /*Note: "nc0001" through "ncFFFF" are also valid signatures defined using macro icNColorSpaceSig()*/
+ /*Note: "mc0001" through "mcFFFF" are also valid signatures defined using macro icNColorSpaceSig()*/
+ icSigMCSDataEnd = 0x6d63FFFF, // provide clues to UBSan
+
+ icSigMCSMaxEnumData = 0xFFFFFFFF,
} icMaterialColorSignature;
#define icGetColorSpaceType(sig) ((icColorSpaceSignature)(((icUInt32Number)sig)&0xffff0000))
Source: GitHub Commit
Detection Methods for CVE-2026-21505
Indicators of Compromise
- Unexpected application crashes when processing ICC profile files
- UndefinedBehaviorSanitizer (UBSan) reports indicating invalid enum values in iccDEV library functions
- Core dumps or crash logs referencing icMaterialColorSignature or related color profile processing functions
Detection Strategies
- Enable UndefinedBehaviorSanitizer during development and testing to detect invalid enum value usage
- Implement file integrity monitoring for ICC profile directories to detect potentially malicious files
- Deploy application crash monitoring to identify patterns of denial of service attempts
- Audit applications for iccDEV library usage and verify version numbers against vulnerable releases
Monitoring Recommendations
- Monitor application logs for abnormal terminations during color profile processing operations
- Implement input validation at the application layer before passing ICC profiles to iccDEV
- Track iccDEV library versions across the environment using software composition analysis tools
- Configure endpoint detection to alert on repeated application crashes related to color management
How to Mitigate CVE-2026-21505
Immediate Actions Required
- Upgrade iccDEV to version 2.3.1.2 or later immediately
- Audit all applications in your environment that depend on iccDEV libraries
- Restrict processing of ICC profiles from untrusted sources until patching is complete
- Enable compiler sanitizers in development environments to catch similar issues
Patch Information
The vulnerability has been patched in iccDEV version 2.3.1.2. The fix explicitly specifies icUInt32Number as the underlying type for the icMaterialColorSignature enum and adds sentinel values (icSigMCSDataEnd and icSigMCSMaxEnumData) to provide proper bounds for sanitization tools.
For detailed patch information, refer to:
Workarounds
- Implement input validation to reject ICC profiles from untrusted sources before processing
- Deploy application sandboxing to limit the impact of crashes caused by malformed profiles
- Compile applications with UndefinedBehaviorSanitizer to trap invalid enum values during testing
- Consider implementing file type verification for ICC profiles before passing to processing functions
# Verify iccDEV version in your environment
# Check for vulnerable versions and update package managers accordingly
pkg-config --modversion iccDEV
# Compile with UBSan for testing environments
export CXXFLAGS="-fsanitize=undefined -fno-sanitize-recover=all"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
