Oracle Linux: CVE-2019-19203: ELSA-2020-3662: php:7.3 security, bug fix, and enhancement update (MODERATE) (Multiple Advisories)

An issue was discovered in Oniguruma 6.x before 6.9.4_rc2. In the function gb18030_mbc_enc_len in file gb18030.c, a UChar pointer is dereferenced without checking if it passed the end of the matched string. This leads to a heap-based buffer over-read.
An out-of-bounds read vulnerability was found in the way Oniguruma handled regular expressions with GB18030 character encoding. A UChar pointer is dereferenced without checking if it passed the end of the matched string, leading to a heap-based buffer over-read. A remote attacker could abuse this flaw by providing a malformed regular expression that, when processed by an application linked to Oniguruma, might crash the application causing a denial of service.