diff --git a/lib/libc/net/if_indextoname.c b/lib/libc/net/if_indextoname.c
index 454823e5e01..e7ccb422dc6 100644
--- a/lib/libc/net/if_indextoname.c
+++ b/lib/libc/net/if_indextoname.c
@@ -40,7 +40,7 @@ __FBSDID("$FreeBSD$");
 #include <errno.h>
 
 /*
- * From RFC 2533:
+ * From RFC 2553:
  *
  * The second function maps an interface index into its corresponding
  * name.