diff -Ebru OpenPBS_2_3_16/src/iff/iff2.c OpenPBS_2_3_16.patched/src/iff/iff2.c
--- OpenPBS_2_3_16/src/iff/iff2.c	2001-12-05 01:38:08.000000000 +0100
+++ OpenPBS_2_3_16.patched/src/iff/iff2.c	2006-09-27 16:01:28.000000000 +0200
@@ -106,6 +106,14 @@
 
 static char ident[] = "@(#) $RCSfile: iff2.c,v $ $Revision: 2.2.10.8 $";
 
+#define _GNU_SOURCE
+#include <unistd.h>
+
+// we are lazy and do not check for errors here :(
+uid_t __euid;
+#define DROPEUID __euid = geteuid(); setresuid(getuid(), getuid(), geteuid())
+#define RESTOREEUID setresuid(getuid(), __euid, getuid())
+
 int pbs_errno;
 struct connect_handle connection[NCONNECTS];
 
@@ -135,6 +143,8 @@
 	extern int   optind;
 	extern char *optarg;
 
+	DROPEUID;
+
 	/* Need to unset LOCALDOMAIN if set, want local host name */
 
 	for (i=0; envp[i]; ++i) {
@@ -176,12 +186,15 @@
 	if ((servport = atoi(argv[++optind])) <= 0)
 		return (1);
 
+	RESTOREEUID;	// we need a reserved port here
 	for (i=0; i<10; i++) {
 		sock = client_to_svr(hostaddr, (unsigned int)servport, 1);
 		if (sock != PBS_NET_RC_RETRY)
 			break;
 		sleep(1);
 	}
+	DROPEUID;
+
 	if (sock < 0) {
 		fprintf(stderr, "pbs_iff: cannot connect to host\n");
 		return (4);
Nur in OpenPBS_2_3_16.patched/src/iff: iff2.c~.
diff -Ebru OpenPBS_2_3_16/src/mom_rcp/rcp.c OpenPBS_2_3_16.patched/src/mom_rcp/rcp.c
--- OpenPBS_2_3_16/src/mom_rcp/rcp.c	1998-10-15 01:09:08.000000000 +0200
+++ OpenPBS_2_3_16.patched/src/mom_rcp/rcp.c	2006-09-27 15:06:30.000000000 +0200
@@ -135,7 +135,8 @@
 #ifdef	KERBEROS
 		case 'k':
 			dest_realm = dst_realm_buf;
-			(void)strncpy(dst_realm_buf, optarg, REALM_SZ);
+			memset(dst_realm_buf, 0, REALM_SZ);
+			(void)strncpy(dst_realm_buf, optarg, REALM_SZ-1);
 			break;
 #ifdef CRYPT
 		case 'x':
@@ -197,13 +198,15 @@
 
 	if (fflag) {			/* Follow "protocol", send data. */
 		(void)response();
-		(void)setuid(userid);
+		if(setuid(userid) != 0)
+			errx(1, "can't change to uid %d", (int)userid);
 		source(argc, argv);
 		exit(errs);
 	}
 
 	if (tflag) {			/* Receive data. */
-		(void)setuid(userid);
+		if(setuid(userid) != 0)
+			errx(1, "can't change to uid %d", (int)userid);
 		sink(argc, argv);
 		exit(errs);
 	}
@@ -637,6 +640,9 @@
 
 		for (size = 0; isdigit(*cp);)
 			size = size * 10 + (*cp++ - '0');
+		if(size < 0) // integer overflow, more can happen in the loop but lets avoid testing for the sake of performance
+			SCREWUP("size becomes too big and swapped");
+
 		if (*cp++ != ' ')
 			SCREWUP("size not delimited");
 		if (targisdir) {
@@ -644,12 +650,12 @@
 			static int cursize;
 			size_t need;
 
-			need = strlen(targ) + strlen(cp) + 250;
+			need = strlen(targ) + strlen(cp) + 250; // b/c this might overflow (very unlikely) we use sNprintf() later
 			if (need > cursize) {
-				if (!(namebuf = malloc(need)))
+				if (!(namebuf = malloc(need))) // will not set a limit here
 					run_err("%s", strerror(errno));
 			}
-			(void)sprintf(namebuf, "%s%s%s", targ,
+			(void)snprintf(namebuf, need, "%s%s%s", targ,
 			    *targ ? "/" : "", cp);
 			np = namebuf;
 		} else
@@ -818,6 +824,8 @@
 {
 	char ch, *cp, resp, rbuf[BUFSIZ];
 
+	memset(rbuf, 0, BUFSIZ);
+
 	if (read(rem, &resp, sizeof(resp)) != sizeof(resp))
 		lostconn(0);
 
@@ -834,7 +842,7 @@
 			if (read(rem, &ch, sizeof(ch)) != sizeof(ch))
 				lostconn(0);
 			*cp++ = ch;
-		} while (cp < &rbuf[BUFSIZ] && ch != '\n');
+		} while (cp < &rbuf[BUFSIZ-1] && ch != '\n');
 
 		if (!iamremote)
 			(void)write(STDERR_FILENO, rbuf, cp - rbuf);
diff -Ebru OpenPBS_2_3_16/src/mom_rcp/util.c OpenPBS_2_3_16.patched/src/mom_rcp/util.c
--- OpenPBS_2_3_16/src/mom_rcp/util.c	1998-10-15 01:09:13.000000000 +0200
+++ OpenPBS_2_3_16.patched/src/mom_rcp/util.c	2006-09-27 14:52:38.000000000 +0200
@@ -120,7 +120,11 @@
 		return (127);
 	
 	case 0:
-		(void)setuid(userid);
+		if(setuid(userid) != 0)
+		{
+			run_err("setuid(%u): %s", userid, strerror(errno));
+			_exit(127);
+		}
 		execl(_PATH_BSHELL, "sh", "-c", s, NULL);
 		_exit(127);
 	}
@@ -129,6 +133,8 @@
 	return (status);
 }
 
+// arbitrary limit
+#define UPPERLIMIT 2^20
 BUF *
 allocbuf(bp, fd, blksize)
 	BUF *bp;
@@ -141,6 +147,12 @@
 		run_err("fstat: %s", strerror(errno));
 		return (0);
 	}
+
+	if(blksize <= 0 || blksize > UPPERLIMIT)
+	{
+		run_err("blksize value is ivalid (either <= 0 or > %u)\n", UPPERLIMIT);
+		return 0;
+	}
 	size = (((int)stb.st_blksize + blksize - 1) / blksize) * blksize;
 	if (size == 0)
 		size = blksize;