An issue was discovered in PHP 7.3.x before 7.3.1. An invalid multibyte string supplied as an argument to the mb_split() function in ext/mbstring/php_mbregex.c can cause PHP to execute memcpy() with a negative argument, which could read and write past buffers allocated for the data.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9025
Reference (s):
- https://security.netapp.com/advisory/ntap-20190321-0001/
- https://bugs.php.net/bug.php?id=77367