Fixing a possible strcat on a NULL pointer

diff --git a/ext/imap/php_imap.c b/ext/imap/php_imap.c
index de4bb1e16258f73533e7101e08536016f271cd2c..4bfcafdad54c9fb14a7bdaef1493b6b30b94aa0f 100644 (file)
--- a/ext/imap/php_imap.c
+++ b/ext/imap/php_imap.c
@@ -3222,7 +3222,8 @@ int _php_imap_mail(char *to, char *subject, char *message, char *headers, char *
                }
        }
 
-       strcat(bufferHeader, headers);
+       if (headers && *headers)
+               strcat(bufferHeader, headers);
 
        if (TSendMail(INI_STR("SMTP"), &tsm_err, &tsm_errmsg, bufferHeader, subject, bufferTo, message, bufferCc, bufferBcc, rpath) != SUCCESS) {
                if (tsm_errmsg) {