A critical out-of-bounds write vulnerability (CVE-2025-68670, CVSS 9.1) in xrdp allows unauthenticated remote code execution or denial of service via malicious domain information during connection. A high-severity flaw (CVE-2024-39917, CVSS 7.2) enables unlimited login attempts by bypassing the MaxLoginRetry parameter. Affected versions are xrdp prior to 0.10.5, and users must upgrade to xrdp version 0.10.5 or later to remediate these issues.
It was discovered that xrdp incorrectly handled bounds checking when processing user domain information during the connection sequence. An unauthenticated remote attacker could use this issue to cause xrdp to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2025-68670) It was discovered that xrdp did not correctly enforce the maximum number of login attempts configured by the MaxLoginRetry parameter. A remote attacker could use this issue to perform an unlimited number of login attempts. (CVE-2024-39917) It was discovered that xrdp did not perform bounds checking when accessing font glyphs. Since some of this data is controllable by the user, a remote attacker could use this issue to cause xrdp to read out of bounds. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-42822) It was discovered that xrdp did not properly handle session establishment errors. A remote attacker could use this issue to bypass OS-level session restrictions enforced by PAM, such as the maximum number of concurrent sessions per user. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-40184)