loose lips sink ships

Etymology
Shortening of a wartime slogan from World War II.

Proverb

 * 1) Saying too much or releasing confidential information can have dangerous consequences.

Translations

 * Chinese:
 * Mandarin:
 * Finnish: älä puhu sivu suun
 * French: propos inconsidérés, bateaux coulés
 * German:
 * Japanese:
 * Mongolian: амсар сэтэрхий аяганд цай бүү хий, ам сул хүнд нууцаа бүү дэлгэ
 * Polish: nieostrożne gadanie zatapia statki
 * Russian: болту́н — нахо́дка для шпио́на
 * Spanish: por la boca muere el pez, palabra y piedra suelta no tiene vuelta, palabra de boca, piedra de honda