RS - 2026 - 091 Hardware Enforcement of Agentic Authority: Why Software Kill Switches Fail

The cybersecurity industry has converged on a flawed assumption: that autonomous AI agents can be safely controlled through software-level kill switches, API authorisation, and post-hoc evaluation frameworks. This paper argues that software enforcement is structurally inadequate against adversarial agents. Because software controls share the same trust boundary as the compromised agent they are meant to govern, they are vulnerable to neutralisation, state corruption, and timing exploitation. We present empirical results from a five-vector attack surface analysis of M99 DOOMSDAY PROTOCOL, a production-grade software kill switch implementation, using T308 SPECTER REGICIDE. The testing revealed three exploitable vulnerabilities in a well-architected kill switch: an authentication bypass on the arming endpoint, a reliably exploitable arm/execute race condition (3/3 attempts successful), and API flooding degrading termination reliability. All three were confirmed fixed and re-verified in the same laboratory session. The findings demonstrate that even architecturally sound software kill switches remain subject to implementation-layer vulnerabilities that require ongoing adversarial validation to surface. We present the Red Specter Hardware Enforcement Stack: a three-pillar architecture consisting of KILLKEY (hardware presence interlock), TRUEGATE (zero standing authority via ephemeral intent-binding), and DEADBOLT (backup control-plane interlock). We demonstrate that hardware enforcement is the only durable control architecture for high-consequence agentic operations, providing both physical execution certainty and court-admissible cryptographic evidence.