Bug 2565927 (CVE-2026-121406)

Summary: CVE-2026-121406 freerdp: freerdp: Denial of Service via zero-output graphics payload
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in FreeRDP. A malicious Remote Desktop Protocol (RDP) server can cause a Denial of Service (DoS) by sending a specially crafted graphics payload that decompresses to zero bytes. Because the client fails to account for empty output data before initializing its internal stream buffer, an internal check fails, causing the client application to crash and terminate the active session.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2566785, 2566786    
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Description OSIDB Bzimport 2026-11-03 16:26:58 UTC
FreeRDP before 3.32.2 allows a client assertion abort because rdpgfx_on_data_received rejects only negative zgfx_decompress status and passes the resulting null output pointer to Stream_StaticConstInit. A malicious RDP server can send a zero-output ZGFX payload on the RDPGFX channel after session activation to terminate the client.