Bug 2567902 (CVE-2026-121952)

Summary: CVE-2026-121952 freerdp: freerdp: Out-of-bounds write in proxy bitmap cache v2 capability handling
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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. An out-of-bounds write vulnerability exists in freerdp-proxy when processing Bitmap Cache v2 capability sets. The proxy accepts a client-declared numCellCaches value below five and later indexes the bitmap cache cell array at fixed positions 0 through 4. A client that connects to the proxy and completes capability exchange can cause heap corruption, disclosure of adjacent heap contents to the backend server, or a crash of the proxy process.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-05 22:35:06 UTC 
FreeRDP before 3.32.2 has an out-of-bounds write in the proxy because rdp_read_bitmap_cache_v2_capability_set rejects only numCellCaches values above 5, yet the bitmap cache v2 cell array is later accessed at fixed indices 0 through 4. A client connecting to the proxy can declare fewer than five cell caches in its Confirm Active, causing heap corruption, heap data leakage to the backend, or a crash.