X : Security Vulnerabilities, CVEs, Published In 2013 (Memory corruption) CVSS score >= 2

Use-after-free vulnerability in the doImageText function in dix/dixfonts.c in the xorg-server module before 1.14.4 in X.Org X11 allows remote authenticated users to cause a denial of service (daemon crash) or possibly execute arbitrary code via a crafted ImageText request that triggers memory-allocation failure.

X.Org xdm 1.1.10, 1.1.11, and possibly other versions, when performing authentication using certain implementations of the crypt API function that can return NULL, allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by attempting to log into an account whose password field contains invalid characters, as demonstrated using the crypt function from glibc 2.17 and later with (1) the "!" character in the salt portion of a password field or (2) a password that has been encrypted using DES or MD5 in FIPS-140 mode.

X.org libXt 1.1.3 and earlier does not check the return value of the XGetWindowProperty function, which allows X servers to trigger use of an uninitialized pointer and memory corruption via vectors related to the (1) ReqCleanup, (2) HandleSelectionEvents, (3) ReqTimedOut, (4) HandleNormal, and (5) HandleSelectionReplies functions.