CVE-2026-44978
xrdp: Unchecked FIPS padding length in standard RDP Security causes heap out-of-bounds read in HMAC verification
Description
xrdp is an open source RDP server. Versions 0.10.6 and prior contain a heap out-of-bounds read vulnerability within the FIPS-specific receive paths. This vulnerability does not affect the default configuration of xrdp. The vulnerability is only exploitable when the security layer is set to security_layer=negotiate or security_layer=rdp, and the crypto level is changed to crypt_level=fips in xrdp.ini. In this specific non-default mode, the server fails to validate the FIPS padding length field, leading to a pointer underflow and a subsequent negative length calculation. An unauthenticated remote attacker can exploit this by sending a crafted FIPS-protected PDU, causing a heap out-of-bounds read that results in a process crash and denial of service (DoS). However, since xrdp forks a new process for each connection by default, an out-of-bounds read causing a process crash is unlikely to bring down the entire xrdp service. This issue has been fixed in version 0.10.6.1.
INFO
Published Date :
July 20, 2026, 5:17 p.m.
Last Modified :
Oct. 24, 2026, 8:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update xrdp to version 0.10.6.1.
- Ensure FIPS mode is disabled if using older versions.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-44978.
| URL | Resource |
|---|---|
| https://github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1 | Release Notes |
| https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-9cg5-f7m7-ppvj | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-44978 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-2026-44978
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-2026-44978 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-44978 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.
-
CVE Translated by [email protected]
Oct. 24, 2026
Action Type Old Value New Value Added Translation Title: xrdp de neutrinolabs, Description: xrdp es un servidor RDP de código abierto. Las versiones 0.10.6 y anteriores contienen una vulnerabilidad de lectura fuera de límites de heap dentro de las rutas de recepción específicas de FIPS. Esta vulnerabilidad no afecta la configuración predeterminada de xrdp. La vulnerabilidad solo es explotable cuando la capa de seguridad se establece en security_layer=negotiate o security_layer=rdp, y el nivel criptográfico se cambia a crypt_level=fips en xrdp.ini. En este modo específico no predeterminado, el servidor no valida el campo de longitud de relleno FIPS, lo que lleva a un desbordamiento inferior de puntero y un cálculo de longitud negativo subsiguiente. Un atacante remoto no autenticado puede explotar esto enviando una PDU protegida por FIPS manipulada, causando una lectura fuera de límites de heap que resulta en un fallo del proceso y denegación de servicio (DoS). Sin embargo, dado que xrdp bifurca un nuevo proceso para cada conexión por defecto, una lectura fuera de límites que causa un fallo del proceso es poco probable que derribe todo el servicio xrdp. Este problema ha sido solucionado en la versión 0.10.6.1. -
Initial Analysis by [email protected]
Jul. 22, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:neutrinolabs:xrdp:*:*:*:*:*:*:*:* versions up to (excluding) 0.10.6.1 Added Reference Type GitHub, Inc.: https://github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-9cg5-f7m7-ppvj Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 21, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-44978', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-21T16:03:54.447257Z'} -
New CVE Received by [email protected]
Jul. 20, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'neutrinolabs', 'product': 'xrdp', 'versions': [{'status': 'affected', 'version': '< 0.10.6.1'}]}] Added Description xrdp is an open source RDP server. Versions 0.10.6 and prior contain a heap out-of-bounds read vulnerability within the FIPS-specific receive paths. This vulnerability does not affect the default configuration of xrdp. The vulnerability is only exploitable when the security layer is set to security_layer=negotiate or security_layer=rdp, and the crypto level is changed to crypt_level=fips in xrdp.ini. In this specific non-default mode, the server fails to validate the FIPS padding length field, leading to a pointer underflow and a subsequent negative length calculation. An unauthenticated remote attacker can exploit this by sending a crafted FIPS-protected PDU, causing a heap out-of-bounds read that results in a process crash and denial of service (DoS). However, since xrdp forks a new process for each connection by default, an out-of-bounds read causing a process crash is unlikely to bring down the entire xrdp service. This issue has been fixed in version 0.10.6.1. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-20 Added CWE CWE-125 Added Reference https://github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1 Added Reference https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-9cg5-f7m7-ppvj