--- tmux.c.orig	2010-07-19 07:07:06.311243142 +0200

+++ tmux.c	2010-07-19 07:08:54.969213735 +0200

@@ -185,9 +185,10 @@

 {

 	char		base[MAXPATHLEN], *path;

 	struct stat	sb;

-	u_int		uid;

+	u_int		uid,gid;

 	uid = getuid();

+    gid = getgid();

 	xsnprintf(base, MAXPATHLEN, "%s/tmux-%d", _PATH_TMP, uid);

 	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)

@@ -203,6 +204,9 @@

 		errno = EACCES;

 		return (NULL);

 	}

+    /* drop unnecessary privileges */

+    if (setresgid(gid, gid, gid) != 0)

+        return (NULL);

 	xasprintf(&path, "%s/%s", base, label);

 	return (path);