Vulnerability · Published Sep 3, 2026 · Assigned by VulnCheck

CVE-2026-85089FreeRDP before 3.31.0 Information Disclosure via uninitialized heap memory

Medium 6.5

In plain English

A medium-severity security flaw in FreeRDP from FreeRDP. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.4%top 67.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10freerdp2:3.10.3-12.el10_2.14ALSA-2026:75570
AlmaLinux:10freerdp-devel2:3.10.3-12.el10_2.14ALSA-2026:75570
AlmaLinux:10freerdp-libs2:3.10.3-12.el10_2.14ALSA-2026:75570
AlmaLinux:10freerdp-server2:3.10.3-12.el10_2.14ALSA-2026:75570
AlmaLinux:10libwinpr2:3.10.3-12.el10_2.14ALSA-2026:75570
AlmaLinux:10libwinpr-devel2:3.10.3-12.el10_2.14ALSA-2026:75570
Debian:12freerdp2no fix listedDEBIAN-CVE-2026-85089
Debian:13freerdp3no fix listedDEBIAN-CVE-2026-85089
Debian:14freerdp33.31.0+dfsg-1DEBIAN-CVE-2026-85089
Rocky Linux:10freerdp2:3.10.3-12.el10_2.14RLSA-2026:75570
Ubuntu:22.04:LTSfreerdp2no fix listedUBUNTU-CVE-2026-85089
Ubuntu:24.04:LTSfreerdp33.31.0+dfsg-0ubuntu0.24.04.1UBUNTU-CVE-2026-85089
Ubuntu:26.04:LTSfreerdp33.31.0+dfsg-0ubuntu0.26.04.1UBUNTU-CVE-2026-85089

Affected products (as reported)

VendorProductVersions
FreeRDP FreeRDP 3.0.0 – before 3.31.0

Weakness: CWE-908 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

References