diff --git a/lib/std/crypto/aegis.zig b/lib/std/crypto/aegis.zig
index 01dd5d547b..da09aca351 100644
--- a/lib/std/crypto/aegis.zig
+++ b/lib/std/crypto/aegis.zig
@@ -174,7 +174,7 @@ pub const Aegis128L = struct {
             acc |= (computed_tag[j] ^ tag[j]);
         }
         if (acc != 0) {
-            mem.set(u8, m, 0xaa);
+            @memset(m.ptr, undefined, m.len);
             return error.AuthenticationFailed;
         }
     }
@@ -343,7 +343,7 @@ pub const Aegis256 = struct {
             acc |= (computed_tag[j] ^ tag[j]);
         }
         if (acc != 0) {
-            mem.set(u8, m, 0xaa);
+            @memset(m.ptr, undefined, m.len);
             return error.AuthenticationFailed;
         }
     }
diff --git a/lib/std/crypto/aes_gcm.zig b/lib/std/crypto/aes_gcm.zig
index 30fd37e6a0..6eadcdee2f 100644
--- a/lib/std/crypto/aes_gcm.zig
+++ b/lib/std/crypto/aes_gcm.zig
@@ -91,7 +91,7 @@ fn AesGcm(comptime Aes: anytype) type {
                 acc |= (computed_tag[p] ^ tag[p]);
             }
             if (acc != 0) {
-                mem.set(u8, m, 0xaa);
+                @memset(m.ptr, undefined, m.len);
                 return error.AuthenticationFailed;
             }