CVE-2023-6779: Heap Overflow in glibc syslog via Secondary Buffer Allocation

A heap buffer overflow vulnerability exists in glibc's syslog implementation when the primary static buffer (1024 bytes) is insufficient to hold the formatted header. The vulnerability occurs in the secondary buffer expansion logic where the required allocation size is not computed when the header size exceeds the static buffer. This causes malloc to allocate only 1 byte instead of the required size, leading to a heap overflow when writing the header and message to the undersized buffer.