FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, in ClearCodec, when `glyphData` is present, `clear_decompress` calls `freerdp_image_copy_no_overlap` without validating the destination rectangle, allowing an out-of-bounds read/write via crafted RDPGFX surface updates. A malicious server can trigger a clientโside heap buffer overflow, causing a crash (DoS)
VulnCheck: FreeRDP is
Exploit
CVE-2026-23531
VulnCheck
Update to v3.21.0