Bug 2533911 (CVE-2026-91964)

Summary: CVE-2026-91964 FreeRDP: FreeRDP: Remote code execution via heap buffer overflow in Server Redirection PDU
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. A malicious Remote Desktop Protocol (RDP) server can exploit a heap-based buffer overflow vulnerability in the `nego_send_negotiation_request` function. By sending a specially crafted Server Redirection PDU message with an attacker-controlled `LoadBalanceInfo` field, the server can write an arbitrary-length field into a fixed-size buffer without proper validation. This can lead to a denial of service (client crash) or, when chained with a memory disclosure vulnerability, potentially remote code execution on the client system.
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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: 2534097, 2534099    
Bug Blocks:    

Description OSIDB Bzimport 2026-09-15 15:48:43 UTC 
FreeRDP versions before 3.31.0 contain a heap-based buffer overflow in nego_send_negotiation_request when processing Server Redirection PDU messages with attacker-controlled LoadBalanceInfo fields. A malicious RDP server can trigger the overflow by sending an arbitrary-length field that gets written to a fixed 512-byte buffer without validation, causing client crashes or potential code execution when chained with memory disclosure.