Blind PRNG Hijacking: An Undetectable Integrity-Preserving Attack Against LLM Watermarking
Researchers have discovered SeedHijack, a supply-chain attack that compromises LLM watermarking schemes by hijacking the pseudo-random number generator (PRNG) used in watermark implementation. The attack amplifies watermark signals while remaining undetectable by current defense mechanisms, exposing a critical vulnerability in cryptographic content-provenance systems that assumed PRNG trustworthiness.