arch/x86/kvm/mmu.c in the Linux kernel through 4.13.5, when nested virtualisation is used, does not properly traverse guest pagetable entries to resolve a guest virtual address, which allows L1 guest OS users to execute arbitrary code on the host OS or cause a denial of service (incorrect index during page walking, and host OS crash), aka an "MMU potential stack buffer overrun."
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
| Link | Tags |
|---|---|
| https://access.redhat.com/errata/RHSA-2018:0412 | third party advisory vendor advisory |
| https://access.redhat.com/errata/RHSA-2018:0395 | third party advisory vendor advisory |
| https://patchwork.kernel.org/patch/9996587/ | issue tracking patch vendor advisory |
| https://patchwork.kernel.org/patch/9996579/ | issue tracking patch vendor advisory |
| http://www.securityfocus.com/bid/101267 | vdb entry third party advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=1500380 | issue tracking third party advisory patch |