CVE-2026-33516
Description
A flaw was found in xrdp, an open-source Remote Desktop Protocol (RDP) server. A remote, unauthenticated attacker can exploit an out-of-bounds read vulnerability by sending a specially crafted Confirm Active PDU during the RDP capability exchange. This issue occurs when memory is accessed without proper validation of the buffer length. Successful exploitation could lead to a denial of service, causing the server process to crash, or potentially disclose sensitive information from the server's memory.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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