CVE-2026-91953
FreeRDP versions before 3.31.0 contain a heap buffer overflow vulnerability in nego_send_negotiation_request() that fails to validate the LB_LOAD_BALANCE_INFO field length before writing to a fixed 512-byte buffer. A malicious RDP server or man-in-the-middle can send a Server Redirection PDU with an oversized LB_LOAD_BALANCE_INFO value to overflow the buffer with attacker-controlled content, causing denial of service or heap corruption before authentication completes.
- Published Sep 15, 2026
- CVSS 7.1 high
- 0.5% chance of exploitation in the next 30 days (EPSS)
- Public exploit code is available
- A fix is available