diff --git a/libavutil/tests/aes_ctr.c b/libavutil/tests/aes_ctr.c
index 5af48428aa..6726b00cda 100644
--- a/libavutil/tests/aes_ctr.c
+++ b/libavutil/tests/aes_ctr.c
@@ -19,18 +19,23 @@
 #include <string.h>
 
 #include "libavutil/random_seed.h"
+#include "libavutil/lfg.h"
 #include "libavutil/log.h"
 #include "libavutil/mem_internal.h"
 #include "libavutil/aes_ctr.h"
 
 static const DECLARE_ALIGNED(8, uint8_t, plain)[] = {
+    0x6d, 0x6f, 0x73, 0x74, 0x20, 0x72, 0x61, 0x6e, 0x64, 0x6f,
+    0x6d, 0x6f, 0x73, 0x74, 0x20, 0x72, 0x61, 0x6e, 0x64, 0x6f,
     0x6d, 0x6f, 0x73, 0x74, 0x20, 0x72, 0x61, 0x6e, 0x64, 0x6f,
     0x6d, 0x6f, 0x73, 0x74, 0x20, 0x72, 0x61, 0x6e, 0x64, 0x6f
 };
 
 static const DECLARE_ALIGNED(8, uint8_t, encrypted)[] = {
     0x95, 0xcd, 0x9a, 0x8a, 0x83, 0xa2, 0x1a, 0x84, 0x92, 0xed,
-    0xd6, 0xf2, 0x57, 0x2f, 0x61, 0x98, 0xbc, 0x20, 0x98, 0xee
+    0xd6, 0xf2, 0x57, 0x2f, 0x61, 0x98, 0xbc, 0x20, 0x98, 0xee,
+    0x6c, 0xed, 0x53, 0xae, 0x2f, 0xc4, 0x18, 0x7c, 0xeb, 0x62,
+    0xbb, 0x3a, 0x71, 0x24, 0x22, 0x8c, 0xd9, 0xfa, 0xee, 0x10
 };
 
 static const DECLARE_ALIGNED(8, uint8_t, fixed_iv)[] = {
@@ -44,14 +49,17 @@ static const DECLARE_ALIGNED(8, uint8_t, fixed_key)[] = {
 
 static DECLARE_ALIGNED(8, uint32_t, key)[4];
 
-static DECLARE_ALIGNED(8, uint8_t, tmp)[20];
+static DECLARE_ALIGNED(8, uint8_t, tmp)[40];
 
 int main (void)
 {
     int ret = 1;
+    AVLFG lfg;
     struct AVAESCTR *ae, *ad;
     const uint8_t *iv, *k;
 
+    av_lfg_init(&lfg, av_get_random_seed());
+
     for (int i = 0; i < 2; i++) {
         ae = av_aes_ctr_alloc();
         ad = av_aes_ctr_alloc();
@@ -85,13 +93,30 @@ int main (void)
         iv =   av_aes_ctr_get_iv(ae);
         av_aes_ctr_set_full_iv(ad, iv);
 
-        av_aes_ctr_crypt(ae, tmp, plain, sizeof(tmp));
+        uint8_t *dst = tmp;
+        const uint8_t *src = plain;
+        int left = sizeof(plain);
+        while (left > 0) {
+            int count = (av_lfg_get(&lfg) % left) + 1;
+            av_aes_ctr_crypt(ae, dst, src, count);
+            dst += count;
+            src += count;
+            left -= count;
+        }
         if (i && memcmp(tmp, encrypted, sizeof(tmp)) != 0) {
             av_log(NULL, AV_LOG_ERROR, "test failed\n");
             goto ERROR;
         }
 
-        av_aes_ctr_crypt(ad, tmp, tmp,   sizeof(tmp));
+        dst = tmp;
+        left = sizeof(plain);
+        while (left > 0) {
+            int count = (av_lfg_get(&lfg) % left) + 1;
+            av_aes_ctr_crypt(ad, dst, dst, count);
+            dst += count;
+            left -= count;
+        }
+
         if (memcmp(tmp, plain, sizeof(tmp)) != 0){
             av_log(NULL, AV_LOG_ERROR, "test failed\n");
             goto ERROR;