diff --git a/lib/krb5/pac.c b/lib/krb5/pac.c
index 62e069ea7..ca3cbadef 100644
--- a/lib/krb5/pac.c
+++ b/lib/krb5/pac.c
@@ -409,7 +409,7 @@ verify_checksum(krb5_context context,
     krb5_error_code ret;
     Checksum cksum;
 
-    memset(&cksum, 0, sizof(cksum));
+    memset(&cksum, 0, sizeof(cksum));
 
     sp = krb5_storage_from_mem((char *)data->data + sig->offset_lo,
 			       sig->buffersize);