CVE-2026-109246

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6698
https://www.vulncheck.com/advisories/freerdp-before-3.32.0-shadow-server-divide-by-zero-via-frame-acknowledge-pdu
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6698

Configurations

No configuration.

History

18 Oct 2026, 12:17

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6698 -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6698 -

12 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 17:17

Updated : 2026-10-18 12:17

NVD link : CVE-2026-109246

Mitre link : CVE-2026-109246

CVE.ORG link : CVE-2026-109246

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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