FreeRDP up to 3.20.x gdi_SurfaceToSurface heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in FreeRDP up to 3.20.x. This issue affects the function gdi_SurfaceToSurface. The manipulation results in heap-based overflow. This vulnerability is identified as CVE-2026-23532. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, was found in FreeRDP up to 3.20.x. Affected is the function gdi_SurfaceToSurface. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the FreeRDP client’s `gdi_SurfaceToSurface` path due to a mismatch between destination rectangle clamping and the actual copy size. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-23532 since 01/13/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 297109 (TencentOS Server 4: freerdp (TSSA-2026:0039)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.21.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the databases at Tenable (297109), EUVD (EUVD-2026-3316) and CERT Bund (WID-SEC-2026-0145). Once again VulDB remains the best source for vulnerability data.

Affected

  • Open Source FreeRDP

Productinfo

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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: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / 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: 297109
Nessus Name: TencentOS Server 4: freerdp (TSSA-2026:0039)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: FreeRDP 3.21.0

Timelineinfo

01/13/2026 CVE reserved
01/19/2026 +6 days Advisory disclosed
01/19/2026 +0 days VulDB entry created
01/30/2026 +11 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-fq8c-87hj-7gvr
Status: Confirmed

CVE: CVE-2026-23532 (🔒)
GCVE (CVE): GCVE-0-2026-23532
GCVE (VulDB): GCVE-100-341796
EUVD: 🔒
CERT Bund: WID-SEC-2026-0145 - FreeRDP: Mehrere Schwachstellen ermöglichen DoS und Codeausführung

Entryinfo

Created: 01/19/2026 19:06
Updated: 01/30/2026 01:01
Changes: 01/19/2026 19:06 (69), 01/19/2026 21:51 (1), 01/20/2026 08:33 (1), 01/20/2026 18:14 (7), 01/29/2026 01:43 (11), 01/30/2026 01:01 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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