xrdp is an open source RDP server. Versions 0.10.6 and prior contain a missing bounds check in xrdp, which allows a heap-based buffer overflow when operating in vnc-any mode. The issue 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, leading to 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. This issue has been fixed in version 0.10.6.1.

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.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the processing of Client Control PDUs. During the RDP connection sequence, the parser does not perform sufficient length validation before reading specific data fields from the network stream. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted, truncated Client Control PDU. 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.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a heap-based buffer overflow vulnerability within the virtual channel forwarding mechanism. When forwarding data from a remote client to the internal channel server, the xrdp process utilizes a fixed-size buffer without adequate bounds checking on the incoming payload. An authenticated remote attacker can exploit this flaw by sending a specially crafted virtual channel message that exceeds the buffer capacity, leading to heap memory corruption. This may result in a denial of service or the execution of arbitrary code with the privileges of the xrdp process. This issue has been fixed in version 0.10.6.1.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a timing side-channel vulnerability in the login interface. Due to a discrepancy in response processing times, a remote attacker can infer the existence of a username on the system, leading to unauthorized information disclosure via username enumeration. This issue has been fixed in version 0.10.6.1.

xrdp is an open source RDP server. In versions 0.10.6 and prior, when an authenticated user session is initialized using the Xvnc backend over UNIX domain sockets, the Xvnc process is launched with insufficient authentication mechanisms. A local authenticated attacker could exploit this vulnerability to bypass intended session isolation, allowing them to unauthorizedly view or control the active desktop sessions of other users on the same system. Users using other backends, such as xorgxrdp or Xvnc over TCP sockets, are not affected. This issue has been fixed in version 0.10.6.1.

xrdp is an open source RDP server. In versions 0.10.6 and prior, a n issue was discovered where the software fails to properly validate the totalLength field within the RDP protocol control header during packet reception. An unauthenticated remote attacker can exploit this vulnerability by sending a specially crafted packet that forces the xrdp process or thread into an infinite, CPU-bound loop. Because the internal pointer fails to advance and the deadlock prevention mechanism is bypassed for specific protocol data unit types, the process consumes excessive CPU resources indefinitely. This can render the xrdp service unavailable and potentially lead to system-wide resource exhaustion if multiple malicious connections are established. This issue has been fixed in version 0.10.6.1.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain an integer overflow vulnerability when processing screen update messages within the vnc-any connection mode. A malicious remote VNC server can send crafted image dimensions that cause an integer overflow during memory buffer size calculation, resulting in an undersized allocation. Subsequent processing of the incoming image data using the original oversized parameters leads to an out-of-bounds read. An unauthenticated remote attacker could exploit this flaw to disclose sensitive information from the heap memory or cause a denial of service (DoS) via a process crash. This issue has been fixed in version 0.10.6.1.

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a vulnerability concerning the parsing of Client Security Data within the Client MCS Connect Initial PDU with GCC Conference Create Request during the connection sequence. During the initial capability and security negotiation phase, the parser fails to perform sufficient length validation for the incoming data block. A remote, unauthenticated attacker could potentially exploit this flaw by sending a specially crafted RDP packet containing malformed data. Due to missing bounds checks, the xrdp process may read a small number of bytes beyond the declared data block boundary, potentially disclosing process memory contents that could be combined with other vulnerabilities. This issue has been fixed in version 0.10.6.1.

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.