Context

• node version: v10.15.0
• joi version: v14.0.0
• environment (node, browser): node
• used with (hapi, standalone, ...): standalone
• any other relevant information:

What are you trying to achieve or the steps to reproduce ?

const schema = Joi.string().base64()

const length = 4473955
let data = 'ACAgICAgICApXG4gICAgICAgICDcDdAgICAgIClXbi'
while (data.length < length) {
   data += 'ACAgICAgICApXG4gICAgICAgICDcDdAgICAgIClXbi'
}
data = data.substring(0, length)

const buffer = Buffer.from(data)
const value = buffer.toString('base64')

Which result you had ?

RangeError: Maximum call stack size exceeded

What did you expect ?

const { error } = Joi.validate(value, schema) // NO error should be here