ELF auxiliary vector storage leaks piece of kernel stack. A potential information leak exists in the OpenBSD kernel which could result in data from the kernel stack being leaked to userland via the ELF auxiliary vector.
The problem has been fixed in -current. For 5.9 and 6.0 the following errata patches are available. https://ftp.openbsd.org/pub/OpenBSD/patches/6.0/common/020_exec_elf.patch.sig https://ftp.openbsd.org/pub/OpenBSD/patches/5.9/common/037_exec_elf.patch.sig
