CVE-2023-39356 Missing offset validation leading to Out-of-Bounds Read in FreeRDP

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. In affected versions a missing offset validation may lead to an Out Of Bound Read in the function gdi_multi_opaque_rect. In particular there is no code to validate if the value multi_opaque_rect->numRectangles is less than 45. Looping through multi_opaque_rect->numRectangles without proper boundary checks can lead to Out-of-Bounds Read errors which will likely lead to a crash. This issue has been addressed in versions 2.11.0 and 3.0.0-beta3. Users are advised to upgrade. There are no known workarounds for this vulnerability.