The vulnerability in the given code is related to CWE-787 (Out-of-bounds Write) on line 37. The `memcpy` operation could potentially write beyond the allocated buffer if the total size of decoded base64 data exceeds the allocated size of `*pData`.

Here are five possible patches to address this vulnerability:

Patch 1: Add a size check before memcpy
```c
if (wpos + bplen <= utf8_len) {
    memcpy(&(*pData)[wpos], bptr, bplen);
    wpos += bplen;
} else {
    goto fail;
}
```

Patch 2: Use a safer memory copy function
```c
if (memcpy_s(&(*pData)[wpos], utf8_len - wpos, bptr, bplen) != 0) {
    goto fail;
}
wpos += bplen;
```

Patch 3: Reallocate buffer if needed
```c
if (wpos + bplen > utf8_len) {
    BYTE* new_data = realloc(*pData, wpos + bplen);
    if (!new_data) goto fail;
    *pData = new_data;
    utf8_len = wpos + bplen;
}
memcpy(&(*pData)[wpos], bptr, bplen);
wpos += bplen;
```

Patch 4: Use dynamic allocation for each chunk
```c
BYTE* new_data = realloc(*pData, wpos + bplen);
if (!new_data) goto fail;
*pData = new_data;
memcpy(&(*pData)[wpos], bptr, bplen);
wpos += bplen;
```

Patch 5: Pre-calculate total size and allocate once
```c
// Before the while loop:
size_t total_size = 0;
char* tok_copy = strdup(utf8);
char* tok = strtok(tok_copy, "\r\n");
while (tok) {
    size_t bplen = 0;
    crypto_base64_decode(tok, strlen(tok), NULL, &bplen);
    total_size += bplen;
    tok = strtok(NULL, "\r\n");
}
free(tok_copy);

*pData = calloc(total_size, sizeof(BYTE));
if (!*pData) goto fail;

// Then proceed with the original decoding loop
```

Each of these patches addresses the vulnerability in a different way, either by adding checks, using safer functions, or improving the memory allocation strategy. The choice of patch depends on the specific requirements and constraints of the project.