AES-GCM and ChaCha20-Poly1305 are AEAD constructions. Opening a modified ciphertext fails with an error instead of returning garbage.
AEAD
Authenticated encryption with associated data: one operation that gives confidentiality and tamper detection.
AES-GCM and ChaCha20-Poly1305 are AEAD constructions. Opening a modified ciphertext fails with an error instead of returning garbage.