I'm creating a bloom filter.
The purpose of bloom filters is to tell the enquirer whether a value is either definitely not in the set, or is possibly in the set.
The only attack vector I can think of is:
An attacker has two versions of the bloom filter, the first version containing a set of values and the second version containing that set plus one additional value.
Could the attacker get any information about the newly added value from the (up to 20) hash-derived bits that are set in the second version and clear in the first version?
Are there other attack vectors?
Is there any benefit to using a cryptographically secure hash function when calculating (20) hashes of the value, which are used to set bits in the bloom filter?
In particular, with a non-cryptographic hash function, does prefixing the value with the byte values 0-19, before hashing, to create the 20 hashes, create any form of weakness?