Description
FreeRDP shadow server from 3.0.0 before 3.32.0 dispatches input PDUs during the Confirm Active state before authentication, allowing unauthenticated attackers to inject keyboard input. Attackers can negotiate TLS-only RDP and send an input PDU without Confirm Active to inject synthetic keystrokes into the host user's X11 session via XTEST.
Affected products
freerdp: freerdp
References2
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-m998-cvfm-9… ExploitVendor Advisory
- www.vulncheck.com/advisories/freerdp-shadow-before-3.32.0-pre-a… Third Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 26 · as of 11 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.