This doesn't have to be the case. Start by avoiding C and C++. Use Java (on Android) to write parsers. It is very hard to take a buggy parser written in Java, and to escalate to a memory corruption attack.

If you really can't use a language like Java, write your parser in safe Rust using slices over Vec<u8>. Then run a fuzzer over it. You'll find a few runtime panics, but you're vanishingly unlikely to encounter memory corruption.

Buffer overflows and memory corruption can be almost entirely avoided these days, at a price.