CVE-2023-40186: IntegerOverflow leading to Out-Of-Bound Write Vulnerability in FreeRDP

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-08-31 · updated 2026-06-17
Weakness: CWE-190

Description

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Affected versions are subject to an IntegerOverflow leading to Out-Of-Bound Write Vulnerability in the `gdi_CreateSurface` function. This issue affects FreeRDP based clients only. FreeRDP proxies are not affected as image decoding is not done by a proxy. This issue has been addressed in versions 2.11.0 and 3.0.0-beta3. Users are advised to upgrade. There are no known workarounds for this issue.

Affected products

Debian Linux: 10.0
Fedoraproject Fedora: 37, 38, 39
FreeRDP: before 2.11.0; 3.0.0-beta1, 3.0.0-beta2 — fixed in 2.11.0

How to fix

Upgrade to a fixed version: FreeRDP 2.11.0. Check the vendor advisory for mitigations.

References

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