Oniguruma through 6.9.3, as used in PHP 7.3.x and other products, has a heap-based buffer over-read in str_lower_case_match in regexec.c.
https://bugs.php.net/bug.php?id=78559
https://github.com/kkos/oniguruma/commit/d3e402928b6eb3327f8f7d59a9edfa622fec557b
https://lists.debian.org/debian-lts-announce/2019/12/msg00002.html
Source: MITRE
Published: 2019-11-25
Updated: 2022-08-29
Type: CWE-125
Base Score: 5
Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 10
Severity: MEDIUM
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 3.9
Severity: HIGH