Gossip is always immoral.
Actually, gossip is not mentioned in the Catechism.
Some people confuse gossip with Detraction and Calumny.
Both ARE mentioned it the catechism:
**1753 **A good intention (for example, that of helping one’s neighbor) does not make behavior that is intrinsically disordered, such as lying and calumny, good or just. The end does not justify the means. Thus the condemnation of an innocent person cannot be justified as a legitimate means of saving the nation. On the other hand, an added bad intention (such as vainglory) makes an act evil that, in and of itself, can be good (such as almsgiving).
**2479 **Detraction and calumny destroy the
reputation and honor of one’s neighbor. Honor is the social witness given to human dignity, and everyone enjoys a natural right to the honor of his name and reputation and to respect. Thus, detraction and calumny offend against the virtues of justice and charity.
**2507 **Respect for the reputation and honor of persons forbids all detraction and calumny in word or attitude.
**2477 **
Respect for the reputation of persons forbids every attitude and word likely to cause them unjust injury. He becomes guilty:
- of rash judgment who, even tacitly, assumes as true, without sufficient foundation, the moral fault of a neighbor; - of *detraction *who, without objectively valid reason, discloses another’s faults and failings to persons who did not know them; - of *calumny *who, by remarks contrary to the truth, harms the reputation of others and gives occasion for false judgments concerning them.
**2539 **Envy is a capital sin. It refers to the sadness at the sight of another’s goods and the immoderate desire to acquire them for oneself, even unjustly. When it wishes grave harm to a neighbor it is a mortal sin: St. Augustine saw envy as “*the *diabolical sin.” “From envy are born hatred, detraction, calumny, joy caused by the misfortune of a neighbor, and displeasure caused by his prosperity.”