UDP 3389
Synopsis
- Microsoft Remote Desktop Protocol (RDP) uses UDP port 3389 (RDP-UDP, per MS-RDPEUDP) starting with RDP 8.0 on Windows 8/Windows Server 2012 and later to improve performance for graphics, input, and multimedia.
- Windows Remote Desktop Services/Terminal Services and the standard Windows RDP client (mstsc.exe) use UDP 3389 alongside TCP 3389 when “UDP transport” is available and allowed by firewall policy.
- Microsoft Remote Desktop clients for macOS, iOS, and Android use UDP 3389 when connecting to supported Windows RDS hosts.
- RemoteFX/RemoteApp sessions delivered via RDP on modern Windows Server versions also leverage UDP 3389 as part of the RDP transport.
- Azure Virtual Desktop session hosts can use classic RDP over UDP 3389 between client and host when not using Shortpath alternatives.
- Open-source RDP clients such as FreeRDP use UDP 3389 when the target Windows server supports RDP-UDP.
- Security note: RDP endpoints (often exposing both TCP and UDP 3389) are heavily targeted for scanning, credential brute-force, and exploitation of RDP flaws (e.g., BlueKeep/CVE-2019-0708), so exposure should be restricted or gated.
Observed activity
Last 30 days
Detailed chart