Vulnerability · Published Jul 20, 2026 · Assigned by GitHub_M
CVE-2026-55238xrdp: Malformed Confirm Active capability sets cause out-of-bounds reads
Medium 5.3
In plain English
A medium-severity security flaw in xrdp from neutrinolabs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the processing of RDP Confirm Active PDU, where during the capability negotiation phase, the parser did not perform sufficient length validation for specific capability sets. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted RDP packet containing malformed capability data. Due to missing bounds checks, the xrdp process may perform out-of-bounds memory reads, which can result in the termination of the service (Denial of Service). 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | xrdp | 0.9.21.1-1+deb12u3 | DEBIAN-CVE-2026-55238 |
| Debian:13 | xrdp | 0.10.1-3.1+deb13u2 | DEBIAN-CVE-2026-55238 |
| Debian:14 | xrdp | 0.10.6.1-2 | DEBIAN-CVE-2026-55238 |
| Ubuntu:22.04:LTS | xrdp | no fix listed | UBUNTU-CVE-2026-55238 |
| Ubuntu:24.04:LTS | xrdp | no fix listed | UBUNTU-CVE-2026-55238 |
| Ubuntu:25.10 | xrdp | no fix listed | UBUNTU-CVE-2026-55238 |
| Ubuntu:26.04:LTS | xrdp | no fix listed | UBUNTU-CVE-2026-55238 |
| Ubuntu:26.10 | xrdp | no fix listed | UBUNTU-CVE-2026-55238 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| neutrinolabs | xrdp | < 0.10.6.1 |
Weakness: CWE-126 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
References
- https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-mg8j-x9rw-9xv3 x_refsource_CONFIRM
- https://github.com/neutrinolabs/xrdp/releases/tag/v0.10.6.1 x_refsource_MISC