Linux Segment Limit Vulnerability

This vulnerability has to do with the division of the address space between a user process and the kernel. Because of a bug, if you select a non-standard memory configuration, sometimes user level processes may be given access upto 252Mb of memory that are really part of the kernel. This allows the process to first search for its memory descriptor and then extend it to cover the rest of the kernel memory. It can then search for a task_struct and modify it so its uid is zero (root). This vulnerability is very obscure, only works on that version of linux, and only if you select a non-standard memory configuration.


 

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