--- a/libpurple/protocols/msn/slp.c Sun Oct 17 03:40:26 2010 +0000 +++ b/libpurple/protocols/msn/slp.c Sun Oct 17 03:55:04 2010 +0000 @@ -554,7 +554,7 @@ slpcall->slplink->remote_user); header = (MsnFileContext *)purple_base64_decode(context, &bin_len); - if (bin_len >= sizeof(MsnFileContext) - 1 && + if (header != NULL && bin_len >= sizeof(MsnFileContext) - 1 && (header->version == 2 || (header->version == 3 && header->length == sizeof(MsnFileContext) + 63))) { file_size = GUINT64_FROM_LE(header->file_size);