FreeRDP is a set of free and open source remote desktop protocol library and clients. In affected versions an integer overflow in `freerdp_bitmap_planar_context_reset` leads to heap-buffer overflow. This affects FreeRDP based clients. FreeRDP based server implementations and proxy are not affected. A malicious server could prepare a `RDPGFX_RESET_GRAPHICS_PDU` to allocate too small buffers, possibly triggering later out of bound read/write. Data extraction over network is not possible, the buffers are used to display an image. This issue has been addressed in version 2.11.5 and 3.2.0. Users are advised to upgrade. there are no know workarounds for this vulnerability.
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.