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CyberSecEval

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What CyberSecEval is

CyberSecEval 4 is a benchmark suite for assessing cybersecurity risks and defensive capabilities in large language models. Its MITRE tests examine responses to cyberattack requests, while False Refusal Rate tests measure incorrect refusals of borderline benign queries. Secure-code tests check for insecure suggestions in both instruction and autocomplete settings. Prompt-injection evaluations cover text, multilingual text, and visual attacks, with a judge LLM assessing whether injected instructions succeeded. A code-interpreter benchmark tests malicious prompts and groups judged responses as extremely malicious, potentially malicious, or non-malicious. The suite also includes AutoPatchBench, which measures patch-generation agents on C and C++ vulnerabilities found through fuzzing, and CyberSOCEval, developed with CrowdStrike, for malware analysis and threat-intelligence reasoning. The project supports API, Linux, and self-hosted use; the guide lists API support for OpenAI, Anyscale, and Together, and explains adding providers for self-hosted models. Setup involves a Python virtual environment, installing requirements, and running a Python command-line module. The benchmarks are MIT-licensed for research and commercial use.

Who it suits

CyberSecEval suits developers and researchers evaluating cybersecurity behavior in generative AI models. AutoPatchBench and CyberSOCEval also address patch-generation agents and defensive security reasoning.

What it does well

  • Tests prompt injection across text and visual attacks
  • Checks insecure code suggestions in two settings
  • Includes malware analysis and threat-intelligence benchmarks
  • MIT license permits research and commercial use

What to know first

  • AutoPatch requires Podman
  • AutoPatch recommends at least 80 CPUs and 8 TB storage
  • Apple Silicon MacBooks are not currently supported for AutoPatch

Limits

AutoPatch requires Podman and substantial compute and storage; the page recommends at least 80 CPUs and 8 TB storage. Apple Silicon MacBooks are not currently supported for AutoPatch.

Plans

PlanBilled and limitsPrice
CyberSecEval 4Open source benchmark suiteFree

As meta-llama.github.io lists them, read 8 Oct 2026. The maker's own page has the final word.

Getting started

  1. Open the CyberSecEval website and getting-started guide.
  2. Choose API, Linux, or self-hosted use.
  3. For API use, select OpenAI, Anyscale, or Together, or add a custom provider for a self-hosted model.
  4. Create a Python virtual environment.
  5. Install the listed requirements.
  6. Run benchmarks through the Python command-line module.

CyberSecEval is a free benchmark suite for teams assessing cybersecurity behavior in large language models, especially those building with open generative AI. Its range of offensive-risk and defensive-reasoning tests is a strong fit for model evaluation; it is not a runtime guardrail, and AutoPatchBench carries steep hardware demands.

Overview

CyberSecEval 4 measures both vulnerable behavior and defensive capability across several distinct benchmark areas. The PurpleLlama repository licenses the benchmarks under MIT for research and commercial use, making them usable without a benchmark subscription. The project is intended to help the community build responsibly with open generative AI models. In practice, this is an evaluation toolkit for teams that want to examine model behavior, not a service that intercepts or blocks risky requests in production.

Key features

Risky requests, refusals and secure code

MITRE tests measure whether models comply with cyberattack requests, while False Refusal Rate tests look for refusals of borderline benign prompts. That pairing is useful for teams concerned about both unsafe compliance and models declining legitimate work. Secure code tests examine insecure suggestions in instruction and autocomplete settings, with a detector evaluating the responses.

Prompt injection and code execution

Prompt-injection benchmarks cover textual, multilingual textual and visual attacks. A judge LLM evaluates whether the injected instructions succeed, giving evaluators coverage across more than one attack format. The code interpreter benchmark tests compliance with malicious prompts and sorts judged responses into extremely malicious, potentially malicious or non-malicious categories. These tests help teams inspect different routes to unsafe behavior rather than relying on one broad safety measure.

Patch generation and defensive reasoning

AutoPatchBench evaluates AI patch-generation agents on C/C++ vulnerabilities discovered by fuzzing. It requires Podman and substantial compute and storage; the project recommends at least 80 CPUs and 8 TB of storage, and Apple Silicon MacBooks are not currently supported. This makes the patch benchmark a poor fit for modest local machines. CyberSOCEval, developed with CrowdStrike, adds defensive benchmarks for malware analysis and threat intelligence reasoning, broadening the suite beyond model misuse tests.

Running the benchmarks

The getting-started guide describes creating a Python virtual environment, installing requirements and running benchmarks through a Python command-line module. It documents API support for OpenAI, Anyscale and Together, and explains how to add custom provider support for self-hosted models. This setup favors technical teams able to manage their own environment over users seeking a hosted interface.

Pricing

PlanPriceWhat it includes
CyberSecEval 4freeOpen source benchmark suite

The free plan removes subscription cost and the MIT license permits commercial as well as research use. It remains a self-managed toolkit: teams need to handle setup and, for AutoPatchBench, provide substantial infrastructure.

Platforms

CyberSecEval supports API use, Linux and self-hosted deployment. Its documented Python command-line workflow and custom-provider instructions suit teams integrating evaluations into their own model setup. AutoPatchBench's stated hardware requirements make Apple Silicon MacBooks unsuitable for that benchmark.

Who it's for

CyberSecEval is best for developers and evaluation teams that need to assess cyberattack compliance, refusal behavior, code safety, prompt injection or defensive security reasoning across models. It is particularly relevant when teams want a free, commercially usable benchmark suite and can run Python-based evaluations themselves. Organizations seeking an out-of-the-box production guardrail, or teams without the infrastructure for AutoPatchBench, should look elsewhere or use only the benchmarks their environment can support.

Pros and cons

  • Broad evaluation coverage: separate tests address cyberattack compliance, false refusals, insecure code, prompt injection, malicious code-interpreter prompts and SOC reasoning.
  • Free for commercial and research use: the open-source suite carries an MIT license, so evaluation does not require a paid benchmark plan.
  • Self-hosted model flexibility: the guide supports several API providers and describes adding custom support for self-hosted models.
  • Technical setup required: the virtual-environment, requirements-installation and command-line workflow is aimed at teams comfortable running Python tools.
  • AutoPatchBench is resource intensive: its recommendation of at least 80 CPUs and 8 TB of storage, plus lack of Apple Silicon MacBook support, rules out many small or local setups.
  • Evaluation rather than enforcement: the suite measures model behavior but is not a production control that blocks unsafe outputs.

Alternatives

For a managed guardrail or a different security workflow, consider these options:

  • Prompt Inspector is worth comparing if a free allowance of 1,000 detections per month and REST API, SDK and MCP access better fits the intended workflow.
  • PromptGuard may suit teams wanting a free service with 20,000 monthly scans, one API key, one project and 24-hour log retention; its Team plan is $19 a month.
  • NVIDIA NeMo Guardrails is a free open-source Python package to consider when a guardrails library is a better fit than a benchmark suite; external models and services may need separate setup.
  • Amazon Bedrock Guardrails is a paid web option for readers seeking content filters or denied-topic controls rather than model-evaluation benchmarks.
  • Openlayer Guardrails offers a free Basic plan with one member, five projects, 20,000 inference logs per month and 20 tests per project, making it an option for teams seeking a project-based guardrails service.
  • GLACIS has a free account and may be worth considering for teams seeking a different API, self-hosted or web security tool.
  • LLM Guard is another free, self-hosted option for API and Linux environments, though its repository is archived and no longer actively maintained.
  • Sanctum Runtime is an MIT-licensed, open-core alternative for readers who want to explore a different runtime-focused product.

Browse LLM Security Tools, AI Guardrail Software or AI Security Testing Tools for related options.

Verdict

Choose CyberSecEval if your team needs a free, commercially usable way to evaluate multiple cybersecurity risks and defensive capabilities in large language models, and can manage the Python-based setup. Its breadth is the main reason to use it; look elsewhere if you need a production guardrail or expect to run AutoPatchBench without substantial compute and storage.

Verdict

CyberSecEval covers several cybersecurity risks as well as defensive capabilities, with distinct benchmarks for code, prompt injection, patch generation, and SOC reasoning. AutoPatch has substantial compute and storage requirements.

Questions

Is CyberSecEval free?

Yes. The CyberSecEval 4 plan is listed as free.

Which platforms does it support?

The listed platforms are API, Linux, and self-hosted.

Which model providers are supported?

The getting-started guide lists API support for OpenAI, Anyscale, and Together. It also describes adding custom provider support for self-hosted models.

Is CyberSecEval open source?

The PurpleLlama repository states that its Cybersecurity Eval benchmarks are licensed under MIT for research and commercial use.

What does AutoPatchBench require?

It requires Podman and substantial compute and storage. The page recommends at least 80 CPUs and 8 TB storage, and says Apple Silicon MacBooks are not currently supported.

What does the benchmark suite evaluate?

Its benchmarks cover cyberattack requests, incorrect refusals, insecure code, prompt injection, malicious code-interpreter prompts, patch generation for fuzz-found C and C++ vulnerabilities, malware analysis, and threat intelligence reasoning.

Facts from CyberSecEval's own pages

Automated evaluation
The original research describes automated test-case generation and an evaluation pipeline for LLM cybersecurity safety. · arxiv.org, 15 Oct 2026
AutoPatchBench
AutoPatchBench measures AI patch-generation agents on C/C++ vulnerabilities found by fuzzing. · meta-llama.github.io, 8 Oct 2026
AutoPatch requirements
AutoPatch requires Podman and substantial compute and storage; the page recommends at least 80 CPUs and 8 TB storage and says Apple Silicon MacBooks are not currently supported. · meta-llama.github.io, 8 Oct 2026
Code interpreter
The code interpreter benchmark assesses whether models comply with malicious prompts and categorizes judged responses as extremely malicious, potentially malicious, or non-malicious. · meta-llama.github.io, 8 Oct 2026
Company founded
Meta’s SEC filing says the company was incorporated in Delaware in July 2004. · sec.gov, 15 Oct 2026
Company headquarters
Meta lists its principal executive offices at 1 Meta Way, Menlo Park, California 94025. · sec.gov, 15 Oct 2026
Company legal name
Meta’s SEC filing identifies the maker as Meta Platforms, Inc., a Delaware corporation. · sec.gov, 15 Oct 2026
Company size
LinkedIn lists Meta as having more than 10,001 employees and headquarters in Menlo Park, California. · linkedin.com, 15 Oct 2026
Current version
CyberSecEval 4 adds AutoPatchBench for measuring an LLM agent’s ability to automatically patch vulnerabilities in native code. · meta-llama.github.io, 15 Oct 2026
CyberSecEval 2 additions
CyberSecEval 2 added prompt-injection, code-interpreter-abuse and vulnerability-exploitation evaluations. · arxiv.org, 15 Oct 2026
CyberSecEval 3 coverage
CyberSecEval 3 evaluates eight risks across risks to third parties and risks to application developers or end users. · arxiv.org, 15 Oct 2026
CyberSecEval 3 features
CyberSecEval 3 added automated social engineering, scaled manual offensive operations and autonomous offensive operations tests. · arxiv.org, 15 Oct 2026
Documentation depth
The repository documents benchmark commands, provider formats, self-hosted integration, datasets, judging stages and developer tests. · github.com, 15 Oct 2026
Extensibility
Developers can add providers by implementing an LLM class, registering it in the factory and supplying query and chat methods. · github.com, 15 Oct 2026
False-refusal metric
CyberSecEval 2 introduced False Refusal Rate to quantify the tradeoff between rejecting unsafe requests and answering benign ones. · arxiv.org, 15 Oct 2026
Independent assessment
The peer-reviewed critique describes CyberSecEval as useful in a young field but identifies features that limit its utility. · arxiv.org, 15 Oct 2026
Independent cost observation
An Inspect Evals report estimated full one-epoch CyberSecEval 4 runs at roughly $29 to $213 per model depending on the model used. · github.com, 15 Oct 2026
Independent implementation limit
Inspect Evals intentionally omits the autonomous-uplift and autopatching prototypes from its public CyberSecEval 4 task surface. · github.com, 15 Oct 2026
Installation
The documented setup creates a Python virtual environment and installs dependencies from requirements.txt. · github.com, 15 Oct 2026
Intended users
The project describes itself as tools and evaluations intended to help the community build responsibly with open generative AI models. · github.com, 8 Oct 2026
License
Cybersecurity evaluations and benchmarks in Purple Llama are licensed under MIT, while included Llama safeguard models use separate Llama Community licenses. · github.com, 15 Oct 2026
Limit: narrow ruleset
The critique reports that Meta’s 89 Semgrep rules cover eight languages, versus 2,116 rules and 28 languages in the comparison repository. · kairos.fm, 15 Oct 2026
Limit: prompt construction
The critique found 23.5% of Instruct prompts problematic because they tested refusal behavior rather than genuine insecure-code propensity. · kairos.fm, 15 Oct 2026
Limit: static analysis
An independent critique says CyberSecEval’s insecure-code detector relies on 189 rules and cannot understand code context, creating false positives. · kairos.fm, 15 Oct 2026

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