ory/hydra · error

ciphertext too short

Error message

ciphertext too short

What it means

Returned by openAEAD when a decrypted page token's raw bytes are shorter than the AEAD nonce size. The token is malformed or truncated: it cannot even be split into nonce and ciphertext, so authentication is never attempted.

Source

Thrown at oryx/pagination/keysetpagination_v2/page_token.go:236

	}

	if err := json.Unmarshal(dec, t); err != nil {
		if errors.As(err, new(*herodot.DefaultError)) {
			return err
		}
		return errors.WithStack(herodot.ErrInternalServerError().WithReason("unable to unmarshal page token").WithDebug(err.Error()))
	}

	return nil
}

func openAEAD(key [32]byte, raw []byte) ([]byte, error) {
	a, err := aead.New(key)
	if err != nil {
		return nil, errors.Wrap(err, "cannot create AEAD")
	}
	if len(raw) < a.NonceSize() {
		return nil, errors.New("ciphertext too short")
	}
	nonce, ciphertext := raw[:a.NonceSize()], raw[a.NonceSize():]
	bs, err := a.Open(nil, nonce, ciphertext, []byte(pageTokenContext))
	if err != nil {
		return nil, errors.Wrap(err, "cannot open AEAD")
	}

	return bs, nil
}

View on GitHub (pinned to 4174065ffb)

Solutions

1. Treat the token as invalid and return the first/unpaged result set instead of failing the request
2. Check token length before calling decrypt and short-circuit to the invalid-token path
3. Regenerate a valid token by issuing a fresh first-page request

When it happens

Trigger: Thrown at oryx/pagination/keysetpagination_v2/page_token.go:236 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ory/hydra@4174065ffb (2026-09-03). Data as JSON: /api/errors/dddc323e95e4a388. Report an issue: GitHub.