EXPOSURES › CVE-2026-55194
CVE-2026-55194
CRITICALFreeRDP's heap corruption flaw in response reassembly allows remote code execution via malicious RDP traffic.
A malicious TS Gateway can exploit CVE-2026-55194 to crash the FreeRDP client or execute arbitrary code through heap corruption. DIB organizations must patch FreeRDP to 3.27.0 or later immediately, as this critical vulnerability enables remote code execution and aligns with the vendor's severe track record of memory corruption flaws.
Shame score — A critical RCE flaw in a widely used RDP client that permits remote code execution via malicious traffic, reflecting the vendor's severe track record of memory corruption vulnerabilities.
▸ RECOMMENDED ACTION Remote code execution — patch the affected products on priority.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, rpc_client_recv_fragment in libfreerdp/core/gateway/rpc_client.c ensures the response reassembly stream capacity using only the server-declared alloc_hint rather than the actual StubLength about to be written. A malicious TS Gateway can send a PTYPE_RESPONSE with a small alloc_hint and a much larger frag_length, causing Stream_Write to copy attacker-controlled stub data beyond the 4096-byte pdu->s buffer. This can crash the client and may permit code execution through heap corruption. This issue is fixed in version 3.27.0.