xrdp: Heap buffer overflow in EGFX channel

xrdp is an open source RDP server. Versions through 0.10.5 have a heap-based buffer overflow in the EGFX (graphics dynamic virtual channel) implementation due to insufficient validation of client-controlled size parameters, allowing an out-of-bounds write via crafted PDUs. Pre-authentication exploitation can crash the process, while post-authentication exploitation may achieve remote code execution. This issue has been fixed in version 0.10.6. If users are unable to immediately update, they should run xrdp as a non-privileged user (default since 0.10.2) to limit the impact of successful exploitation.