[XML-RPC] XML error: No memory at line 8, column 18

Issue summary

When open the body of a huge message via XML-RPC on another host you may get XML error No memory.

Steps to reproduce

Setup two servers to work together via XML-RPC.
Send email with size 9Mb+.
Open the body of the message on another host (where the message is not stored).

Expected result

View content of the message like always.

Actual result

Error: Invalid return payload: enable debugging to examine incoming payload (XML error: No memory at line 8, column 18)

HEADER: date: Fri, 12 Jul 2019 15:59:53 GMT
HEADER: server: Apache
HEADER: x-powered-by: PHP/7.2.19
HEADER: x-xss-protection: 1; mode=block
HEADER: x-frame-options: SAMEORIGIN
HEADER: x-content-type-options: nosniff
HEADER: set-cookie: PHPSESSID=XXXXXXXXXXXXXXXXXXXXXXX; path=/; HttpOnly
HEADER: expires: Thu, 19 Nov 1981 08:52:00 GMT
HEADER: cache-control: no-store, no-cache, must-revalidate
HEADER: pragma: no-cache
HEADER: vary: Accept-Encoding
HEADER: content-encoding: gzip
HEADER: content-length: 9898790
HEADER: content-type: text/xml;charset=UTF-8
COOKIE: PHPSESSID=XXXXXXXXXXXXXXXXXXXXXXX

XML error: No memory at line 8, column 18Error: (error06) Invalid return payload: enable debugging to examine incoming payload (XML error: No memory at line 8, column 18)

Installation

Version and method

MailWatch Version: v1.2.7-dev
Install type: EFA 3.0.2.6 https://efa-project.org
Updated from an older MailWatch or fresh install: vendor (EFA)

Server configuration

Operation System: CentOS 6.10
PHP version: php-7.2.20-1.el6.remi.x86_64
Database: MariaDB-server-10.4.6-1.el7.centos.x86_64 (dedicated DB host)
Mail Server: Postfix
Used web server: httpd-2.2.15-69.el6.centos.x86_64

Client configuration

Operation System: Windows 10
Browser: Firefox 67

References about the issue

LIBXML_PARSEHUGE https://php.net/manual/en/libxml.constants.php
https://stackoverflow.com/questions/19152613/

mailwatch / MailWatch

[XML-RPC] XML error: No memory at line 8, column 18 #1151