CVE-2023-38545: Heap overflow in curl SOCKS5 proxy response handling

Heap buffer overflow in libcurl's SOCKS5 proxy implementation when handling malicious server responses. A rogue SOCKS5 proxy server can send a crafted response with an excessively large domain name length field, causing curl to attempt reading more bytes than the allocated heap buffer can hold. This leads to heap memory corruption and potential code execution.