diff --git a/lib/pop3.c b/lib/pop3.c
index 03ea7efaf7..8da045e483 100644
--- a/lib/pop3.c
+++ b/lib/pop3.c
@@ -732,7 +732,7 @@ static CURLcode pop3_done(struct connectdata *conn, CURLcode status,
     result = status;      /* use the already set error code */
   }
 
-  free(pop3c->mailbox);
+  Curl_safefree(pop3c->mailbox);
   pop3c->mailbox = NULL;
 
   /* clear these for next connection */