Open secret
By extension: something that is already known and public, and is not really a secret.
(Modern Hebrew)
Translation
Expression (Hebrew)
סוֹד גָּלוּי
Definition (Hebrew)
בְּהַשְׁאָלָה: דָּבָר שֶׁכְּבָר יָדוּעַ וְהִתְפַּרְסֵם וְאֵינוֹ בְּגֶדֶר סוֹד.
(הָעִבְרִית הַחֲדָשָׁה)