diff --git a/dlls/rsaenh/tests/rsaenh.c b/dlls/rsaenh/tests/rsaenh.c
index a13ca8e4b5a..5fe0033446c 100644
--- a/dlls/rsaenh/tests/rsaenh.c
+++ b/dlls/rsaenh/tests/rsaenh.c
@@ -476,7 +476,7 @@ static void test_hashes(void)
     ok(result, "CryptReleaseContext failed 0x%08x\n", GetLastError());
 
     SetLastError(0xdeadbeef);
-    result = CryptHashData(hHash, (BYTE *)"data", sizeof("data"), 0);
+    result = CryptHashData(hHash, (const BYTE *)"data", sizeof("data"), 0);
     error = GetLastError();
     ok(!result, "CryptHashData succeeded\n");
     ok(error == ERROR_INVALID_PARAMETER, "expected ERROR_INVALID_PARAMETER got %u\n", error);
@@ -493,7 +493,7 @@ static void test_hashes(void)
     result = CryptCreateHash(hProv, CALG_SHA1, 0, 0, &hHash);
     ok(result, "CryptCreateHash failed 0x%08x\n", GetLastError());
 
-    result = CryptHashData(hHash, (BYTE *)"data", sizeof("data"), 0);
+    result = CryptHashData(hHash, (const BYTE *)"data", sizeof("data"), 0);
     ok(result, "CryptHashData failed 0x%08x\n", GetLastError());
 
     result = CryptDuplicateHash(hHash, NULL, 0, &hHashClone);
@@ -504,7 +504,7 @@ static void test_hashes(void)
     ok(result, "CryptGetHashParam failed 0x%08x\n", GetLastError());
 
     /* add data after duplicating the hash */
-    result = CryptHashData(hHash, (BYTE *)"more data", sizeof("more data"), 0);
+    result = CryptHashData(hHash, (const BYTE *)"more data", sizeof("more data"), 0);
     ok(result, "CryptHashData failed 0x%08x\n", GetLastError());
 
     result = CryptDestroyHash(hHash);