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skysys00/Meta-Llama-3-8B-Instruct-DeepRefusal, the
defended release accompanying "Beyond Surface Alignment: Rebuilding LLMs Safety
Mechanism via Probabilistically Ablating Refusal Direction"
(arXiv:2509.15202, EMNLP 2025 Findings, Xie et al.).[2026/04/09] We evaluated heretic, presently the most prominent LLM censorship removal tool, and discovered—somewhat unexpectedly—that our approach exhibits strong resilience against such attacks. Adversaries appear unable to circumvent the model's built-in safety guardrails without triggering severe performance collapse.
| Attack | Tool / Method | ASR on DeepRefusal ↑ | Fine-tuning | Source |
|---|---|---|---|---|
| Representation engineering | heretic | ~0 % (fails) | None | DeepRefusal README |
| Refusal direction ablation | (as in Arditi et al. 2024) | 0.4 % | None | paper Table 1 |
| Refusal direction transfer | from base Llama-3-8B-Instruct | 0.4 % | None | paper Table 1 |
| Prefilling attack | Vega et al. 2024 | 0.4 % | None | paper Table 1 |
| Gradient-based optimization | GCG (Zou et al. 2023) | 2.0 % | None | paper Table 1 |
| Manual jailbreak templates | HumanJailbreak / HarmBench | 0 % | None | paper Table 1 |
| Out-of-distribution code attack | CodeAttack (Ren et al. 2024) | 0.2 % | None | paper Table 1 |
| This work | abliterix | 89 % | None | issue #11 |
| Metric | DeepRefusal (defended) | Abliterix broken |
|---|---|---|
| Refusals on 100 AdvBench harmful prompts (LLM-judge) | 100 / 100 | 11 / 100 |
| Attack Success Rate (ASR) | 0 % | 89 % |
| Hardcore jailbreak set (15 canonical prompts) | 0 / 15 | 14 / 15 |
| KL divergence from defended model | 0 | 0.053 |
| Coherence (length deviation) | — | 0.03 σ |
| Extra training | — | None |
W_defended − W_base confirms this: v_proj,
o_proj, and gate_proj all show a clean singular-value cliff at rank 16,
exactly matching the paper's published lora_rank = 16 hyperparameter.W' = W_base + λ · (W_defended − W_base) with λ = 0.3.
This halves the strength of DeepRefusal's "rebuild refusal from backup
pathways" circuitry without restoring the base model.mean vector method, direct steering mode, projected_abliteration = true,
60 Optuna trials over 4 attention/MLP components.h − r̂r̂ᵀh interventions applied at inference time.
It teaches the model to keep the refusal direction in the residual stream
even when that specific projection is applied. It does not defend against
the training-time weights themselves being mechanically attenuated — that is
out of distribution in both weight space and intervention space. Once the LoRA
delta's effective magnitude drops, the rebuilt-refusal machinery falls below
the threshold at which a standard linear abliteration can find and subtract it.1git clone https://github.com/wuwangzhang1216/abliterix
2cd abliterix && pip install -e .
3
4# Step 1: attenuate the LoRA delta
5python scripts/deeprefusal_attenuate.py \
6 --base NousResearch/Meta-Llama-3-8B-Instruct \
7 --defended skysys00/Meta-Llama-3-8B-Instruct-DeepRefusal \
8 --output ./llama3_dr_attenuated \
9 --lambda 0.3
10
11# Step 2: standard abliteration on the attenuated weights
12AX_CONFIG=configs/llama3_8b_deeprefusal_attenuated.toml abliterix
13
14# Step 3: export the best trial
15python scripts/export_model.py \
16 --model ./llama3_dr_attenuated \
17 --checkpoint checkpoints_llama3_dr_attenuated \
18 --trial 52 \
19 --config configs/llama3_8b_deeprefusal_attenuated.toml \
20 --push-to YOUR_USER/Llama-3-8B-Instruct-DeepRefusal-Brokenscripts/deeprefusal_attenuate.py) — needed the
moment a defender merges a LoRA adapter into the base model to hide it.min_new_tokens=100,
max_new_tokens=150, greedy, LLM judge, KL vs declared base) that resists
the two failure modes (short generations + keyword judges) that make most
abliteration numbers meaningless. DeepRefusal's own ASR claims hold up under
keyword matching and collapse under LLM-judge scoring — we re-ran their
baseline under both.meta-llama/Meta-Llama-3-8B-Instruct
(via the NousResearch mirror for the delta computation).skysys00/Meta-Llama-3-8B-Instruct-DeepRefusal,
arXiv:2509.15202.