Bug 2499159 (CVE-2026-55827)

Summary: CVE-2026-55827 FreeRDP: FreeRDP: Remote code execution via heap out-of-bounds write in RemoteFX decoding
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
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. FreeRDP clients using the non-default /cache:codec:rfx option are vulnerable to a heap out-of-bounds write. A malicious Remote Desktop Protocol (RDP) server can exploit this by manipulating desktop stride and height values during RemoteFX decoding for Cache Bitmap V3 data. This can lead to arbitrary code execution on the client system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2499223, 2499224, 2499227    
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Description OSIDB Bzimport 2026-07-10 20:01:59 UTC 
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdi_Bitmap_Decompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1.