CVE-2026-23531
Published: Jan 19, 2026
Modified: Jan 20, 2026
Description
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 client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
| Vendor | Product | Versions |
|---|---|---|
FreeRDP | FreeRDP | affected < 3.21.0 |
Weaknesses (CWE)
References
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