CVE-2026-21675: iccDEV Use After Free Vulnerability

CVE-2026-21675 Overview

A Use After Free vulnerability has been identified in iccDEV, a popular library and toolset for working with ICC color management profiles. The vulnerability exists in the CIccXform::Create() function within versions 2.3.1 and below, where the hint object is deleted prematurely while still being referenced. This memory corruption issue can be exploited remotely without authentication, potentially leading to arbitrary code execution, information disclosure, or denial of service.

Critical Impact

This Use After Free vulnerability in iccDEV allows remote attackers to exploit memory corruption in the color profile processing functionality, potentially achieving arbitrary code execution or causing application crashes in systems that process ICC color profiles.

Affected Products

• iccDEV versions 2.3.1 and below
• Applications and systems utilizing iccDEV libraries for ICC color profile processing
• Software integrating iccDEV color management functionality

Discovery Timeline

• January 6, 2026 - CVE CVE-2026-21675 published to NVD
• January 8, 2026 - Last updated in NVD database

Technical Details for CVE-2026-21675

Vulnerability Analysis

The vulnerability is a classic Use After Free condition that occurs in the ICC color management transform creation workflow. When processing color profiles with named color hints, the CIccXform::Create() function improperly manages memory by deleting the pNamedColorHint object via DeleteHint() while the hint manager still maintains ownership of the object. This creates a dangling pointer scenario where subsequent operations may attempt to access the freed memory region.

The flaw is particularly dangerous because it can be triggered remotely through the processing of maliciously crafted ICC color profiles. Since ICC profiles are commonly embedded in image files and documents, an attacker could craft a malicious file that, when processed by an application using the vulnerable iccDEV library, triggers the memory corruption.

Root Cause

The root cause stems from incorrect memory ownership semantics in the hint management system. When AddHint() is called on the hint manager, ownership of the hint object transfers to the manager. However, the vulnerable code subsequently called DeleteHint() to explicitly delete the hint, not recognizing that the hint manager had already assumed ownership responsibility. This double-ownership confusion leads to the Use After Free condition when the hint manager later attempts to access or clean up the already-freed hint object.

Attack Vector

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can craft a malicious ICC color profile containing specific named color configurations that trigger the vulnerable code path in CIccXform::Create(). When an application using the vulnerable iccDEV library processes this profile, the Use After Free condition is triggered.

Attack scenarios include:

• Embedding malicious ICC profiles in image files (JPEG, PNG, TIFF)
• Sending crafted color profiles through document processing pipelines
• Uploading malicious images to web applications that perform color profile processing

The following patch shows how the vulnerability was remediated by removing the erroneous DeleteHint() call:

         pNamedColorHint->csSpectralPcs = pProfile->m_Header.spectralPCS;
         pNamedColorHint->spectralRange = pProfile->m_Header.spectralRange;
         pNamedColorHint->biSpectralRange = pProfile->m_Header.biSpectralRange;
-				if (pHintManager) {
-					pHintManager->AddHint(pNamedColorHint);
-					rv = CIccXformCreator::CreateXform(icXformTypeNamedColor, pTag, pHintManager);
-					pHintManager->DeleteHint(pNamedColorHint);
-				}
-				else {
-					CIccCreateXformHintManager HintManager;
-					HintManager.AddHint(pNamedColorHint);
-					rv = CIccXformCreator::CreateXform(icXformTypeNamedColor, pTag, &HintManager);
-				}
+        
+        if (pHintManager) {
+          pHintManager->AddHint(pNamedColorHint);
+          rv = CIccXformCreator::CreateXform(icXformTypeNamedColor, pTag, pHintManager);
+//	      pHintManager->DeleteHint(pNamedColorHint);    // hint manager takes ownership, we should not delete
+        }
+        else {
+          CIccCreateXformHintManager HintManager;
+          HintManager.AddHint(pNamedColorHint);
+          rv = CIccXformCreator::CreateXform(icXformTypeNamedColor, pTag, &HintManager);
+        }

         if (pProfile->m_Header.spectralPCS)
           bUseSpectralPCS = true;

Source: GitHub Commit Details

Detection Methods for CVE-2026-21675

Indicators of Compromise

• Unexpected application crashes in processes handling ICC color profiles
• Abnormal memory access patterns in iccDEV library functions, particularly in CIccXform::Create() and related transform creation routines
• Core dumps or crash reports indicating memory corruption in color profile processing

Detection Strategies

• Monitor applications using iccDEV for segmentation faults or access violations during ICC profile processing
• Implement runtime memory sanitizers (AddressSanitizer, Valgrind) in development and testing environments to detect Use After Free conditions
• Deploy file inspection rules to identify anomalous ICC profile structures in uploaded or processed files
• Audit application dependencies to identify systems running iccDEV versions 2.3.1 or earlier

Monitoring Recommendations

• Enable verbose logging for color profile processing operations in applications utilizing iccDEV
• Implement crash reporting and analysis for applications handling image files and color profiles
• Monitor for unusual patterns in file uploads that may indicate attempts to exploit image processing vulnerabilities
• Set up alerts for repeated crashes in image or document processing services

How to Mitigate CVE-2026-21675

Immediate Actions Required

• Upgrade iccDEV to version 2.3.1.1 or later immediately on all affected systems
• Identify all applications and services that depend on iccDEV libraries and prioritize updates
• Consider temporarily disabling ICC profile processing in critical applications until patches are applied
• Implement input validation and sandboxing for processes that handle untrusted ICC profiles

Patch Information

The vulnerability has been fixed in iccDEV version 2.3.1.1. The fix removes the erroneous DeleteHint() call, ensuring the hint manager properly maintains ownership of hint objects throughout their lifecycle. The patch is available via the GitHub commit. Additional details about the vulnerability and fix can be found in the GitHub Security Advisory GHSA-wcwx-794g-g78f.

Workarounds

• Isolate ICC profile processing in sandboxed environments to limit the impact of potential exploitation
• Implement strict input validation to reject malformed or suspicious ICC color profiles before processing
• Deploy application-level firewalls or content inspection to filter potentially malicious image files containing embedded ICC profiles
• Restrict network access for services that process ICC color profiles where possible

# Example: Check installed iccDEV version and update
# Check current version
pkg-config --modversion iccDEV

# Update to patched version 2.3.1.1
git clone https://github.com/InternationalColorConsortium/iccDEV.git
cd iccDEV
git checkout v2.3.1.1
mkdir build && cd build
cmake ..
make && sudo make install