Bug 2527811 (CVE-2026-85089)

Summary: CVE-2026-85089 FreeRDP: freerdp-proxy: FreeRDP: Information disclosure via uninitialized heap memory in Save Session Info PDU
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in FreeRDP. This vulnerability allows a remote attacker with low privileges to disclose sensitive information from the server or proxy process memory to a downstream client. This occurs because certain functions responsible for writing Save Session Info Protocol Data Units (PDUs) use Stream_Seek instead of Stream_Zero for reserved padding fields, leading to the transmission of uninitialized heap memory that may contain cleartext credentials from previous sessions.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-03 01:11:19 UTC 
FreeRDP versions 3.0.0 through 3.30.0 (before 3.31.0) transmit uninitialized heap memory in Save Session Info PDU reserved padding fields. Three PDU writers in libfreerdp/core/info.c (rdp_write_logon_info_v2, rdp_write_logon_info_plain, and rdp_write_logon_info_ex) use Stream_Seek instead of Stream_Zero for reserved pad bytes (up to 576 bytes), leaving previously freed heap contents in the outgoing PDU. Because the send buffer is allocated with malloc (not zeroed), stale heap data — which may include cleartext credentials from prior sessions — can be sent to the receiving peer. FreeRDP-based servers using rdpUpdate::SaveSessionInfo and freerdp-proxy (which forwards these PDUs) are affected, allowing disclosure of server/proxy process memory to a downstream client.