diff --git a/configure.ac b/configure.ac
index 33c151e..d9390cf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -73,6 +73,9 @@
 AC_PATH_PROG(DOXYGEN,doxygen,false)
 AM_CONDITIONAL(HAVE_DOXYGEN, test $DOXYGEN != false && test "x$doxygen" = "xyes")
 
+# check for syscal fallback on glibc < 2.25 - can be removed once glibc version requirement is bumped
+AC_CHECK_DECLS([SYS_getrandom], [], [], [[#include <sys/syscall.h>]])
+
 # The following test is taken from WebKit's webkit.m4
 saved_CFLAGS="$CFLAGS"
 CFLAGS="$CFLAGS -fvisibility=hidden "
diff --git a/include/osmocom/gsm/gsm_utils.h b/include/osmocom/gsm/gsm_utils.h
index bfcef08..83e29ca 100644
--- a/include/osmocom/gsm/gsm_utils.h
+++ b/include/osmocom/gsm/gsm_utils.h
@@ -38,6 +38,9 @@
 
 #define GSM_MAX_FN	(26*51*2048)
 
+/* Max length of random identifier which can be requested via osmo_get_rand_id() */
+#define OSMO_MAX_RAND_ID_LEN 16
+
 struct gsm_time {
 	uint32_t	fn;	/* FN count */
 	uint16_t	t1;	/* FN div (26*51) */
@@ -60,6 +63,8 @@
 const char *gsm_band_name(enum gsm_band band);
 enum gsm_band gsm_band_parse(const char *mhz);
 
+int osmo_get_rand_id(uint8_t *out, size_t len);
+
 /*!
  * Decode a sequence of GSM 03.38 encoded 7 bit characters.
  *
diff --git a/src/gsm/gsm_utils.c b/src/gsm/gsm_utils.c
index 477f076..f572c64 100644
--- a/src/gsm/gsm_utils.c
+++ b/src/gsm/gsm_utils.c
@@ -91,9 +91,18 @@
 #include <errno.h>
 #include <ctype.h>
 #include <inttypes.h>
+#include <time.h>
+#include <unistd.h>
 
 #include "../../config.h"
 
+/* FIXME: this can be removed once we bump glibc requirements to 2.25: */
+#if defined(__GLIBC__) && (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 25)
+#include <linux/random.h>
+#elif HAVE_DECL_SYS_GETRANDOM
+#include <sys/syscall.h>
+#endif
+
 /* ETSI GSM 03.38 6.2.1 and 6.2.1.1 default alphabet
  * Greek symbols at hex positions 0x10 and 0x12-0x1a
  * left out as they can't be handled with a char and
@@ -387,6 +396,45 @@
 	return y;
 }
 
+/*! Generate random identifier
+ *  We use /dev/urandom (default when GRND_RANDOM flag is not set).
+ *  Both /dev/(u)random numbers are coming from the same CSPRNG anyway (at least on GNU/Linux >= 4.8).
+ *  See also RFC4086.
+ *  \param[out] out Buffer to be filled with random data
+ *  \param[in] len Number of random bytes required
+ *  \returns 0 on success, or a negative error code on error.
+ */
+int osmo_get_rand_id(uint8_t *out, size_t len)
+{
+	int rc;
+
+	/* this function is intended for generating short identifiers only, not arbitrary-length random data */
+	if (len > OSMO_MAX_RAND_ID_LEN)
+               return -E2BIG;
+
+#if defined(__GLIBC__) && (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 25)
+	rc = getrandom(out, len, GRND_NONBLOCK);
+#elif HAVE_DECL_SYS_GETRANDOM
+#pragma message ("Using direct syscall access for getrandom(): consider upgrading to glibc >= 2.25")
+	/* FIXME: this can be removed once we bump glibc requirements to 2.25: */
+	rc = syscall(SYS_getrandom, out, len, GRND_NONBLOCK);
+#else
+#pragma message ("Secure random unavailable: calls to osmo_get_rand_id() will always fail!")
+	return -ENOTSUP;
+#endif
+	/* getrandom() failed entirely: */
+	if (rc < 0)
+		return -errno;
+
+	/* getrandom() failed partially due to signal interruption:
+	   this should never happen (according to getrandom(2)) as long as OSMO_MAX_RAND_ID_LEN < 256
+	   because we do not set GRND_RANDOM but it's better to be paranoid and check anyway */
+	if (rc != len)
+               return -EAGAIN;
+
+	return 0;
+}
+
 /*! Build the RSL uplink measurement IE (3GPP TS 08.58 § 9.3.25)
  *  \param[in] mru Unidirectional measurement report structure
  *  \param[in] dtxd_used Indicates if DTXd was used during measurement report
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 95b2ca9..5598859 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -39,6 +39,7 @@
 
 osmo_sitype_strs;
 osmo_c4;
+osmo_get_rand_id;
 bitvec_add_range1024;
 comp128;
 comp128v2;
diff --git a/utils/osmo-auc-gen.c b/utils/osmo-auc-gen.c
index 1f5c838..9d1215c 100644
--- a/utils/osmo-auc-gen.c
+++ b/utils/osmo-auc-gen.c
@@ -34,6 +34,7 @@
 
 #include <osmocom/crypt/auth.h>
 #include <osmocom/core/utils.h>
+#include <osmocom/gsm/gsm_utils.h>
 
 static void dump_triplets_dat(struct osmo_auth_vector *vec)
 {
@@ -247,14 +248,11 @@
 	}
 
 	if (!rand_is_set) {
-		int i;
-		printf("WARNING: We're using really weak random numbers!\n\n");
-		srand(time(NULL));
-
-		for (i = 0; i < 4; ++i) {
-			uint32_t r;
-			r = rand();
-			memcpy(&_rand[i*4], &r, 4);
+		rc = osmo_get_rand_id(_rand, 16);
+		if (rc < 0) {
+			fprintf(stderr, "\nError: unable to obtain secure random numbers: %s!\n",
+				strerror(-rc));
+			exit(3);
 		}
 	}