The chunk_split function in string.c in PHP 5.2.3 does not properly calculate the needed buffer size due to precision loss when performing integer arithmetic with floating point numbers, which has unknown attack vectors and impact, possibly resulting in a heap-based buffer overflow. NOTE: this is due to an incomplete fix for CVE-2007-2872.
建议您更新当前系统或软件至最新版，完成漏洞的修复。