The Apache2 component in PHP before 5.6.38, 7.0.x before 7.0.32, 7.1.x before 7.1.22, and 7.2.x before 7.2.10 allows XSS via the body of a "Transfer-Encoding: chunked" request, because the bucket brigade is mishandled in the php_handler function in sapi/apache2handler/sapi_apache2.c.
http://php.net/ChangeLog-5.php
http://php.net/ChangeLog-7.php
https://access.redhat.com/errata/RHSA-2019:2519
https://bugs.php.net/bug.php?id=76582
https://github.com/php/php-src/commit/23b057742e3cf199612fa8050ae86cae675e214e
https://lists.debian.org/debian-lts-announce/2018/09/msg00020.html
https://security.gentoo.org/glsa/201812-01
https://security.netapp.com/advisory/ntap-20180924-0001/
Source: MITRE
Published: 2018-09-16
Updated: 2019-08-19
Type: CWE-79
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 6.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Impact Score: 2.7
Exploitability Score: 2.8
Severity: MEDIUM