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CVE-2026-41252 neutrinolabs CVE debrief

CVE-2026-41252 is a critical vulnerability in xrdp, an open-source RDP server. The issue is caused by a missing bounds check, leading to a heap-based buffer overflow when operating in vnc-any mode. This occurs during the handling of RFB protocol color map messages from a VNC server, where incoming color indices are not properly validated. A malicious VNC server can exploit this flaw by sending crafted messages with out-of-range values, resulting in an out-of-bounds write on the heap. This memory corruption can result in a denial of service (DoS) or potentially allow remote code execution (RCE) prior to authentication. The vulnerability has been fixed in version 0.10.6.1.

Vendor
neutrinolabs
Product
xrdp
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-20
Original CVE updated
2026-07-22
Advisory published
2026-07-20
Advisory updated
2026-07-22

Who should care

Users of xrdp versions 0.10.6 and prior should be concerned about this vulnerability, as it can lead to a denial of service (DoS) or potentially allow remote code execution (RCE) prior to authentication. This is particularly critical for systems that expose xrdp to untrusted networks or allow connections from untrusted sources.

Technical summary

The vulnerability is caused by a missing bounds check in xrdp when operating in vnc-any mode. Specifically, during the handling of RFB protocol color map messages from a VNC server, incoming color indices are not properly validated. This allows a malicious VNC server to send crafted messages with out-of-range values, leading to an out-of-bounds write on the heap. The memory corruption resulting from this can cause a denial of service (DoS) or potentially allow remote code execution (RCE) prior to authentication. The issue has been addressed in version 0.10.6.1.

Defensive priority

High

Recommended defensive actions

  • Upgrade xrdp to version 0.10.6.1 or later
  • Restrict access to xrdp from untrusted networks or sources
  • Monitor xrdp logs for suspicious activity
  • Implement additional security controls, such as network segmentation or intrusion detection systems
  • Perform vulnerability scanning to identify exposed systems
  • Review asset inventory for xrdp deployments
  • Establish a rollback plan for emergency change windows

Evidence notes

The CVE record was published on 2026-07-20T17:17:08.310Z and was last modified on 2026-07-22T20:05:07.110Z. The NVD entry is currently Analyzed. The vulnerability has a CVSS score of 9.8 and a severity of CRITICAL.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-20T17:17:08.310Z and has not been modified since then. The NVD entry is currently Analyzed.