FreeRDP up to 3.22.x rail_window_free xfAppWindow use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in FreeRDP up to 3.22.x. This vulnerability affects the function rail_window_free. This manipulation of the argument xfAppWindow causes use after free. This vulnerability is registered as CVE-2026-26986. Remote exploitation of the attack is possible. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in FreeRDP up to 3.22.x and classified as critical. Affected by this vulnerability is the function rail_window_free. The manipulation of the argument xfAppWindow with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-26986 since 02/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 299997 (Linux Distros Unpatched Vulnerability : CVE-2026-26986), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.23.0 eliminates this vulnerability. Applying the patch b4f0f0a18fe53aa8d47d062f91471f4e9c5e0d51 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (299997) and CERT Bund (WID-SEC-2026-0514). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source FreeRDP

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 299997
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-26986

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: FreeRDP 3.23.0
Patch: b4f0f0a18fe53aa8d47d062f91471f4e9c5e0d51

Timelineinfo

02/17/2026 CVE reserved
02/26/2026 +9 days Advisory disclosed
02/26/2026 +0 days VulDB entry created
05/14/2026 +76 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-crqx-g6x5-rx47
Status: Confirmed

CVE: CVE-2026-26986 (🔒)
GCVE (CVE): GCVE-0-2026-26986
GCVE (VulDB): GCVE-100-347845
CERT Bund: WID-SEC-2026-0514 - FreeRDP: Mehrere Schwachstellen

Entryinfo

Created: 02/26/2026 01:13
Updated: 05/14/2026 00:22
Changes: 02/26/2026 01:13 (71), 02/26/2026 19:53 (7), 02/28/2026 19:08 (2), 03/01/2026 06:07 (13), 05/14/2026 00:22 (1)
Complete: 🔍
Cache ID: 216::103

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