FreeRDP up to 3.20.x freerdp_bitmap_decompress_planar nSrcWidth/nSrcHeight 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 described as critical has been identified in FreeRDP up to 3.20.x. This affects the function freerdp_bitmap_decompress_planar. Executing a manipulation of the argument nSrcWidth/nSrcHeight can lead to heap-based overflow. The identification of this vulnerability is CVE-2026-23530. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in FreeRDP up to 3.20.x. This vulnerability affects the function freerdp_bitmap_decompress_planar. The manipulation of the argument nSrcWidth/nSrcHeight with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is 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(). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0,`freerdp_bitmap_decompress_planar` does not validate `nSrcWidth`/`nSrcHeight` against `planar->maxWidth`/`maxHeight` before RLE decode. 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 available at github.com. This vulnerability was named CVE-2026-23530 since 01/13/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

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-2026-3311) and CERT Bund (WID-SEC-2026-0145). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • 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: 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-r4hv-852m-fq7p
Status: Confirmed

CVE: CVE-2026-23530 (🔒)
GCVE (CVE): GCVE-0-2026-23530
GCVE (VulDB): GCVE-100-341794
EUVD: 🔒
CERT Bund: WID-SEC-2026-0145 - FreeRDP: Mehrere Schwachstellen ermöglichen DoS und Codeausführung

Entryinfo

Created: 01/19/2026 19:05
Updated: 01/30/2026 01:58
Changes: 01/19/2026 19:05 (70), 01/19/2026 21:51 (1), 01/20/2026 07:28 (1), 01/20/2026 11:51 (7), 01/29/2026 01:43 (11), 01/30/2026 01:58 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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