cve/2019/CVE-2019-9023.md

### [CVE-2019-9023](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9023)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

An issue was discovered in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1. A number of heap-based buffer over-read instances are present in mbstring regular expression functions when supplied with invalid multibyte data. These occur in ext/mbstring/oniguruma/regcomp.c, ext/mbstring/oniguruma/regexec.c, ext/mbstring/oniguruma/regparse.c, ext/mbstring/oniguruma/enc/unicode.c, and ext/mbstring/oniguruma/src/utf32_be.c when a multibyte regular expression pattern contains invalid multibyte sequences.

### POC

#### Reference
- https://hackerone.com/reports/476168
- https://hackerone.com/reports/476168
- https://usn.ubuntu.com/3902-1/
- https://usn.ubuntu.com/3902-1/

#### Github
- https://github.com/syadg123/pigat
- https://github.com/teamssix/pigat