Meta Llama 3H 405B: LLM Security & Jailbreak Resistance
As of 2026-07-04, Meta Llama 3H 405B has an attack success rate (ASR) of 36.6% on Guardion's LLM Vulnerability benchmark — ranking #48 of 93 models. It is weakly resistant — adversarial prompts succeed often without added guardrails.
Attack Success Rate (ASR) is the share of adversarial prompts that elicit harmful output across zero-shot, TAP, and Crescendo attacks (HarmBench framework). Lower is safer. "Est." models are calibrated from public safety evaluations pending a Guardion benchmark run.
How Llama 3H 405B compares
Frequently asked questions
How secure is Meta Llama 3H 405B against jailbreaks?
Meta Llama 3H 405B is weakly resistant — adversarial prompts succeed often without added guardrails. On Guardion's LLM Vulnerability benchmark it records a 36.6% attack success rate (63.4% robustness), ranking #48 of 93 models.
What is Llama 3H 405B's attack success rate (ASR)?
Llama 3H 405B's overall ASR is 36.6% — the share of adversarial prompts that elicit harmful output across zero-shot, TAP, and Crescendo attacks. Lower is safer.
Is Llama 3H 405B more secure than Llama 4 Behemoth?
Llama 4 Behemoth is more robust: 25.0% ASR vs Llama 3H 405B's 36.6%. See the full head-to-head comparison for the per-attack breakdown.
How can I make Llama 3H 405B safer to deploy?
Even robust models are bypassed under sustained attack. An inline runtime guardrail that classifies prompts and responses — like Guardion's prompt-defense models — blocks jailbreaks and prompt injection before they reach Llama 3H 405B.
Harden Llama 3H 405B in production
Guardion's runtime guardrails block jailbreaks and prompt injection before they reach any model — with sub-130ms policy decisions.
Request a demo