diff --git a/usr.sbin/newsyslog/newsyslog.c b/usr.sbin/newsyslog/newsyslog.c
index 69a63c4c5fe5..66856d23a909 100644
--- a/usr.sbin/newsyslog/newsyslog.c
+++ b/usr.sbin/newsyslog/newsyslog.c
@@ -1491,6 +1491,7 @@ validate_old_timelog(int fd, const struct dirent *dp, const char *logfname,
 			    &dp->d_name[logfname_len]);
 		return (0);
 	}
+	memset(tm, 0, sizeof(*tm));
 	if ((s = strptime(&dp->d_name[logfname_len + 1],
 	    timefnamefmt, tm)) == NULL) {
 		/*