Description
FreeRDP before 3.32.0 contains a divide-by-zero vulnerability in the freerdp-shadow-cli shadow server: the frame id in a client's Frame Acknowledge PDU is stored without a range check, so the in-flight frame count in shadow_encoder_inflight_frames() can underflow. An authenticated client can acknowledge a frame id one greater than the last frame sent, causing shadow_encoder_create_frame_id() to divide by zero (SIGFPE) and terminate the process, disconnecting all viewers.
Affected products
freerdp: freerdp
References3
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6… ExploitVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6… ExploitVendor Advisory
- www.vulncheck.com/advisories/freerdp-before-3.32.0-shadow-serve… Third Party Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/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: 35 · as of 11 November 2026
- CWE
- CWE-191CWE-369
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.