CVE-2026-33516 xrdp: Pre-authentication out-of-bounds reads in RDP capability and channel parsers

What is CVE-2026-33516?

CVE-2026-33516 is a high-severity vulnerability in neutrinolabs xrdp, published on 17 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

xrdp is an open source RDP server. Versions through 0.10.5 contain an out-of-bounds read vulnerability during the RDP capability exchange phase. The issue occurs when memory is accessed before validating the remaining buffer length. A remote, unauthenticated attacker can trigger this vulnerability by sending a specially crafted Confirm Active PDU. Successful exploitation could lead to a denial of service (process crash) or potential disclosure of sensitive information from the process memory. This issue has been fixed in version 0.10.6.

Weakness: CWE-125

Which versions are affected by CVE-2026-33516?

It affects 1 product.

Products include Neutrinolabs Xrdp.

How do I fix CVE-2026-33516?

Upgrade to a fixed version.

Is CVE-2026-33516 being exploited?

There is no known exploitation of CVE-2026-33516 in the wild and no public exploit code.

Other vulnerabilities in neutrinolabs xrdp

• CVE-2026-41252 xrdp: lib_palette_update Heap Buffer Overflow & RCE Critical 9.8
• CVE-2026-32105 xrdp: RDP MAC signature (dataSignature) never verified on receive — integrity bypass in non-TLS mode Critical 9.3
• CVE-2026-44178 xrdp: Channel Data Forwarding Fixed-Size Buffer Overflow High 8.8
• CVE-2026-32107 xrdp: Fail-open privilege drop in sesexec — child processes may execute as root if setuid fails High 8.8
• CVE-2026-33689 xrdp: Pre-authentication out-of-bounds reads in channel parsers High 8.7

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-33516, GHSA-rvh9-9wm3-28c7, UBUNTU-CVE-2026-33516.