The RBAC functionality in grsecurity before 2.1.11-2.6.24.5 and 2.1.11-2.4.36.2 does not enforce user_transition_deny and user_transition_allow rules for the (1) sys_setfsuid and (2) sys_setfsgid calls, which allows local users to bypass restrictions for those calls.
Unspecified vulnerability in the grsecurity patch has unspecified impact and remote attack vectors, a different vulnerability than the expand_stack vulnerability from the Digital Armaments 20070110 pre-advisory. NOTE: the grsecurity developer has disputed this issue, stating that "the function they claim the vulnerability to be in is a trivial function, which can, and has been, easily checked for any supposed vulnerabilities." The developer also cites a past disclosure that was not proven
Unspecified vulnerability in the expand_stack function in grsecurity PaX allows local users to gain privileges via unspecified vectors. NOTE: the grsecurity developer has disputed this issue, stating that "the function they claim the vulnerability to be in is a trivial function, which can, and has been, easily checked for any supposed vulnerabilities." The developer also cites a past disclosure that was not proven. As of 20070120, the original researcher has released demonstration code
The RBAC functionality in grsecurity before 2.1.8 does not properly handle when the admin role creates a service and then exits the shell without unauthenticating, which causes the service to be restarted with the admin role still active.
grsecurity 1.9.4 for Linux kernel 2.4.18 allows local users to bypass read-only permissions by using mmap to directly map /dev/mem or /dev/kmem to kernel memory.