https://nalar.dev/tags/privilege-boundary/ Recent content in Privilege Boundary on Nalar Hugo en-us Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/no-new-privs-blocks-exec-time-privilege-gain/ Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/no-new-privs-blocks-exec-time-privilege-gain/ <p>A service may need to execute helper programs after it has accepted untrusted input. If one of those programs is set-user-ID, set-group-ID, or carries file capabilities, a normal <code>execve()</code> can cross a privilege boundary even when the calling process itself has no intent to acquire extra authority. Linux <code>no_new_privs</code> changes that transition: once set for a thread, later <code>execve()</code> calls cannot grant privileges that were absent from the caller at the point of execution.</p>