Bug 2549822 (CVE-2026-109246)

Summary:	CVE-2026-109246 freerdp: freerdp: Denial of Service via divide-by-zero error in shadow server
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in FreeRDP. An authenticated client can trigger a Denial of Service (DoS) by sending a specially crafted frame acknowledgment message to the shadow server. Due to missing input validation on the frame identifier, an arithmetic error causes a divide-by-zero condition. This terminates the shadow server process, abruptly disconnecting all active session viewers.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-10-12 16:54:33 UTC

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.