A race condition in perf_event_open() allows local attackers to leak sensitive data from setuid programs. As no relevant locks (in particular the cred_guard_mutex) are held during the ptrace_may_access() call, it is possible for the specified target task to perform an execve() syscall with setuid execution before perf_event_alloc() actually attaches to it, allowing an attacker to bypass the ptrace_may_access() check and the perf_event_exit_task(current) call that is performed in install_exec_creds() during privileged execve() calls. This issue affects kernel versions before 4.8.
Exploitability
AV:LAC:HPR:LUI:NScope
S:UImpact
C:HI:NA:N4.7/CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:NOther