The bufferslowrealign function in HAProxy 1.5.x before 1.5.14 and 1.6-dev does not properly realign a buffer that is used for pending outgoing data, which allows remote attackers to obtain sensitive information (uninitialized memory contents of previous requests) via a crafted request.
The I/O implementation for block devices in the Linux kernel before 2.6.33 does not properly handle the CLONEIO feature, which allows local users to cause a denial of service (I/O instability) by starting multiple processes that share an I/O context.