CVE-2026-23533
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk35th percentile - higher than 35% of all known CVEs
Summary
In FreeRDP prior to version 3.21.0, a client-side heap buffer overflow exists in the RDPGFX ClearCodec decode path. Maliciously crafted residual data causes out-of-bounds writes during color output, potentially leading to a crash and code execution.
Risk Assessment
A malicious RDP server can trigger a client-side heap buffer overflow, causing a denial of service (DoS) and, depending on the heap layout, potential code execution on the client system.
Recommendation
Upgrade FreeRDP to version 3.21.0 or later, which includes a fix for this vulnerability.
Original NVD description (English source)
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the RDPGFX ClearCodec decode path when maliciously crafted residual data causes out-of-bounds writes during color output. 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.