FreeRDP up to 3.30.0 PDU Writer libfreerdp/core/info.c information disclosure

Summaryinfo

A vulnerability has been found in FreeRDP up to 3.30.0 and classified as problematic. This issue affects the function rdp_write_logon_info_v2/rdp_write_logon_info_plain/rdp_write_logon_info_ex of the file libfreerdp/core/info.c of the component PDU Writer. The manipulation leads to information disclosure. This vulnerability is listed as CVE-2026-85089. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in FreeRDP up to 3.30.0. It has been rated as problematic. This issue affects the function rdp_write_logon_info_v2/rdp_write_logon_info_plain/rdp_write_logon_info_ex of the file libfreerdp/core/info.c of the component PDU Writer. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-85089 since 09/03/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 3.31.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-70299). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Remote Access Software

Name

• FreeRDP

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15
• 3.16
• 3.17
• 3.18
• 3.19
• 3.20
• 3.21
• 3.22
• 3.23
• 3.24
• 3.25
• 3.26
• 3.27
• 3.28
• 3.29
• 3.30.0

License

• open-source

Website

• Product: https://github.com/FreeRDP/FreeRDP/

CPE 2.3info

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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