Windows Kernel stack memory disclosure in nt!RtlpCopyLegacyContextX86(CVE-2018-0832)

We have discovered a new Windows kernel memory disclosure vulnerability in the creation and copying of a CONTEXT structure to user-mode memory. Two previous bugs in the nearby code area were reported in issues 1177 and 1311 ; in fact, the problem discussed here appears to be a variant of 1177 but...