5.5
MEDIUM CVSS 4.0
CVE-2026-26986
FreeRDP has heap-use-after-free in rail_window_free
Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `rail_window_free` dereferences a freed `xfAppWindow` pointer during `HashTable_Free` cleanup because `xf_rail_window_common` calls `free(appWindow)` on title allocation failure without first removing the entry from the `railWindows` hash table, leaving a dangling pointer that is freed again on disconnect. Version 3.23.0 fixes the vulnerability.

INFO

Published Date :

Feb. 25, 2026, 10:16 p.m.

Last Modified :

Feb. 25, 2026, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-26986 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Update FreeRDP to version 3.23.0 or later to address memory corruption.
  • Update FreeRDP to version 3.23.0 or later.
  • Apply vendor-supplied patches if available.
  • Recompile the software with the fix.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-26986 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-26986 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-26986 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-26986 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Feb. 25, 2026

    Action Type Old Value New Value
    Added Description FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `rail_window_free` dereferences a freed `xfAppWindow` pointer during `HashTable_Free` cleanup because `xf_rail_window_common` calls `free(appWindow)` on title allocation failure without first removing the entry from the `railWindows` hash table, leaving a dangling pointer that is freed again on disconnect. Version 3.23.0 fixes the vulnerability.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-416
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1230-L1238
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1297
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1316-L1327
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L386-L394
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L395-L399
    Added Reference https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L401-L404
    Added Reference https://github.com/FreeRDP/FreeRDP/commit/b4f0f0a18fe53aa8d47d062f91471f4e9c5e0d51
    Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-crqx-g6x5-rx47
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 5.5
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability