diff --git a/main.c b/main.c
index 74e2706..355cdc3 100644
--- a/main.c
+++ b/main.c
@@ -141,6 +141,8 @@ MAI_CleanupAndExit(void)
   HSH_Finalise();
   LOG_Finalise();
 
+  UTI_ResetGetRandomFunctions();
+
   exit(exit_status);
 }
 
diff --git a/nts_ke_server.c b/nts_ke_server.c
index 1239678..ece1b4c 100644
--- a/nts_ke_server.c
+++ b/nts_ke_server.c
@@ -669,6 +669,8 @@ run_helper(uid_t uid, gid_t gid, int scfilter_level)
   CNF_Finalise();
   LOG_Finalise();
 
+  UTI_ResetGetRandomFunctions();
+
   exit(0);
 }
 
@@ -710,6 +712,8 @@ NKS_PreInitialise(uid_t uid, gid_t gid, int scfilter_level)
 
     is_helper = 1;
 
+    UTI_ResetGetRandomFunctions();
+
     snprintf(prefix, sizeof (prefix), "nks#%d:", i + 1);
     LOG_SetDebugPrefix(prefix);
     LOG_CloseParentFd();
diff --git a/privops.c b/privops.c
index 99de867..3fb5cbd 100644
--- a/privops.c
+++ b/privops.c
@@ -662,6 +662,8 @@ PRV_StartHelper(void)
         close(fd);
     }
 
+    UTI_ResetGetRandomFunctions();
+
     /* ignore signals, the process will exit on OP_QUIT request */
     UTI_SetQuitSignalsHandler(SIG_IGN, 1);
 
diff --git a/test/unit/util.c b/test/unit/util.c
index 4d7a4e8..efd9c5a 100644
--- a/test/unit/util.c
+++ b/test/unit/util.c
@@ -670,6 +670,10 @@ test_unit(void)
     UTI_GetRandomBytesUrandom(buf, j);
     if (j && buf[j - 1] % 2)
       c++;
+    if (random() % 10000 == 0) {
+      UTI_ResetGetRandomFunctions();
+      TEST_CHECK(!urandom_file);
+    }
   }
   TEST_CHECK(c > 46000 && c < 48000);
 
@@ -678,6 +682,12 @@ test_unit(void)
     UTI_GetRandomBytes(buf, j);
     if (j && buf[j - 1] % 2)
       c++;
+    if (random() % 10000 == 0) {
+      UTI_ResetGetRandomFunctions();
+#if HAVE_GETRANDOM
+      TEST_CHECK(getrandom_buf_available == 0);
+#endif
+    }
   }
   TEST_CHECK(c > 46000 && c < 48000);
 
diff --git a/util.c b/util.c
index 69f523d..da99f82 100644
--- a/util.c
+++ b/util.c
@@ -1402,29 +1402,32 @@ UTI_DropRoot(uid_t uid, gid_t gid)
 
 #define DEV_URANDOM "/dev/urandom"
 
+static FILE *urandom_file = NULL;
+
 void
 UTI_GetRandomBytesUrandom(void *buf, unsigned int len)
 {
-  static FILE *f = NULL;
-
-  if (!f)
-    f = UTI_OpenFile(NULL, DEV_URANDOM, NULL, 'R', 0);
-  if (fread(buf, 1, len, f) != len)
+  if (!urandom_file)
+    urandom_file = UTI_OpenFile(NULL, DEV_URANDOM, NULL, 'R', 0);
+  if (fread(buf, 1, len, urandom_file) != len)
     LOG_FATAL("Can't read from %s", DEV_URANDOM);
 }
 
 /* ================================================== */
 
 #ifdef HAVE_GETRANDOM
+
+static unsigned int getrandom_buf_available = 0;
+
 static void
 get_random_bytes_getrandom(char *buf, unsigned int len)
 {
   static char rand_buf[256];
-  static unsigned int available = 0, disabled = 0;
+  static unsigned int disabled = 0;
   unsigned int i;
 
   for (i = 0; i < len; i++) {
-    if (!available) {
+    if (getrandom_buf_available == 0) {
       if (disabled)
         break;
 
@@ -1433,10 +1436,10 @@ get_random_bytes_getrandom(char *buf, unsigned int len)
         break;
       }
 
-      available = sizeof (rand_buf);
+      getrandom_buf_available = sizeof (rand_buf);
     }
 
-    buf[i] = rand_buf[--available];
+    buf[i] = rand_buf[--getrandom_buf_available];
   }
 
   if (i < len)
@@ -1460,6 +1463,20 @@ UTI_GetRandomBytes(void *buf, unsigned int len)
 
 /* ================================================== */
 
+void
+UTI_ResetGetRandomFunctions(void)
+{
+  if (urandom_file) {
+    fclose(urandom_file);
+    urandom_file = NULL;
+  }
+#ifdef HAVE_GETRANDOM
+  getrandom_buf_available = 0;
+#endif
+}
+
+/* ================================================== */
+
 int
 UTI_BytesToHex(const void *buf, unsigned int buf_len, char *hex, unsigned int hex_len)
 {
diff --git a/util.h b/util.h
index f6bf7b9..a57ef9b 100644
--- a/util.h
+++ b/util.h
@@ -224,6 +224,10 @@ extern void UTI_GetRandomBytesUrandom(void *buf, unsigned int len);
    generating long-term keys */
 extern void UTI_GetRandomBytes(void *buf, unsigned int len);
 
+/* Close /dev/urandom and drop any cached data used by the GetRandom functions
+   to prevent forked processes getting the same sequence of random numbers */
+extern void UTI_ResetGetRandomFunctions(void);
+
 /* Print data in hexadecimal format */
 extern int UTI_BytesToHex(const void *buf, unsigned int buf_len, char *hex, unsigned int hex_len);