The IA32 system call emulation functionality in arch/x86/ia32/ia32entry.S in the Linux kernel before 2.6.36-rc4-git2 on the x86_64 platform does not zero extend the %eax register after the 32-bit entry path to ptrace is used, which allows local users to gain privileges by triggering an out-of-bounds access to the system call table using the %rax register. NOTE: this vulnerability exists because of a CVE-2007-4573 regression.

The IA32 system call emulation functionality in Linux kernel 2.4.x and 2.6.x before 2.6.22.7, when running on the x86_64 architecture, does not zero extend the eax register after the 32bit entry path to ptrace is used, which might allow local users to gain privileges by triggering an out-of-bounds access to the system call table using the %RAX register.