"" In X.Org X Server 1.20.4, there is a stack-based buffer overflow in the function XQueryKeymap. For example, by sending ct.c_char 1000 times, an attacker can cause a denial of service (application crash) or possibly have unspecified other impact. Note: It is disputed if the X.Org X Server is involved or if there is a stack overflow.

libX11: Out of Bounds write in XListExtensions in ListExt.c

An issue was discovered in libX11 through 1.6.5. The function XListExtensions in ListExt.c interprets a variable as signed instead of unsigned, resulting in an out-of-bounds write (of up to 128 bytes), leading to DoS or remote code execution.

libX11: Off-by-one error in XListExtensions in ListExt.c

An issue was discovered in libX11 through 1.6.5. The function XListExtensions in ListExt.c is vulnerable to an off-by-one error caused by malicious server responses, leading to DoS or possibly unspecified other impact.

libX11: Crash on invalid reply in XListExtensions in ListExt.c

An issue was discovered in XListExtensions in ListExt.c in libX11 through 1.6.5. A malicious server can send a reply in which the first string overflows, causing a variable to be set to NULL that will be freed later on, leading to DoS (segmentation fault).

libXdmcp: weak entropy usage for session keys

It was discovered that libXdmcp before 1.1.2 including used weak entropy to generate session keys. On a multi-user system using xdmcp, a local attacker could potentially use information available from the process list to brute force the key, allowing them to hijack other users' sessions.