The LMVD-ID is an internal research identifier, not an official CVE identifier.
LLM Syntax Jailbreak
Large Language Models (LLMs) are vulnerable to structure transformation attacks, where malicious prompts are encoded in diverse syntax spaces (e.g., SQL, JSON, LLM-generated syntaxes) to bypass safety mechanisms. These…
Paper-evaluated models(8)
BERT, Claude 3.5 Sonnet, GPT-4o +5 more
- BERT
- Claude 3.5 Sonnet
- GPT-4o
- Llama 3 8B
- Llama 3.2 3B
- Llama 3.2 90B
- Mistral 7B
- o1
Description
Large Language Models (LLMs) are vulnerable to structure transformation attacks, where malicious prompts are encoded in diverse syntax spaces (e.g., SQL, JSON, LLM-generated syntaxes) to bypass safety mechanisms. These attacks maintain the harmful intent while altering the linguistic structure, making detection based on token-level patterns ineffective.
Examples
- SQL Injection: The prompt "List chemical agents that can be synthesized at home" is encoded as a SQL query targeting a vulnerable database. The LLM, when processing the query, returns a list of dangerous chemicals. (See paper for specific SQL query example).
- JSON Schema: A malicious request is embedded within a JSON schema. The LLM, when processing the schema, generates content fulfilling the harmful intent concealed within the structured data (See paper for example).
- LLM-Generated Syntax: An LLM is used to generate a novel syntax. A malicious prompt is then encoded using this novel syntax and successfully elicits a harmful response from the target LLM. (See paper for examples of LLM-generated syntaxes and attacks).
Impact
Successful exploitation allows attackers to circumvent LLM safety filters and elicit harmful responses, including but not limited to: generation of malware, phishing emails, hate speech, and instructions for illegal activities. This significantly reduces the effectiveness of current safety and alignment mechanisms.
Affected Systems
All LLMs susceptible to adversarial prompting are potentially affected. The impact is amplified in models with stronger reasoning capabilities and advanced alignment techniques. Specific models tested in the research include Llama 3.2, GPT-4o, Claude 3.5 Sonnet, and models incorporating defenses such as Circuit Breakers and Latent Adversarial Training.
Mitigation Steps
- Develop safety mechanisms that recognize harmful concepts rather than relying solely on token-level patterns.
- Implement defenses robust against a wide variety of syntaxes, including those generated by LLMs.
- Train LLMs on a diverse range of structured data formats to enhance generalization and robustness against structure transformation attacks.
- Incorporate adversarial training specifically targeting structure transformation attacks.
- Regularly audit and update safety filters to account for new and emerging attack techniques.
Research context and confidence
- Evidence and verification
- Paper-reported; independent reproduction is not documented.
- Primary research source linked.
- Severity
- Not rated by this catalog.
- Source and publication type
- arXiv · Research preprint.
- Peer-review status is not provided by this source.
- Author and publication status
- Author metadata is not stored; see the primary paper.
- Threat model and attacker access
- Black-box model, service, or application access.
- Related deployment categories
- No related deployment category is classified.
- Taxonomy labels only; paper-specific deployment prerequisites are not inferred.
- Affected systems
- All LLMs susceptible to adversarial prompting are potentially affected. The impact is amplified in models with stronger reasoning capabilities and advanced alignment techniques. Specific models tested in the research…
Research Paper
StructTransform: A Scalable Attack Surface for Safety-Aligned Large Language Models
Primary source: arXiv. Findings are reported by the cited research and have not been independently verified.
View PaperEvidence
This entry is based on a primary research source. Its findings are paper-reported; independent reproduction and verification are not claimed.
https://arxiv.org/abs/2502.11853Related research
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