security

General security rules for source code, including protecting secrets, validating input, preventing injection and cross-site scripting, and handling credentials safely.

In plain words
What is it for?
Use them when writing or reviewing code that handles external input, databases, web output, dependencies, secrets, authentication tokens, or security logging.
Why use it?
They reduce common security mistakes such as leaked keys, unsafe database queries, malicious input, exposed sensitive logs, and weak token comparisons.

Cursor rule

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/0xnyk/awesome-agent-cortex/security
Clone the repo
git clone --depth 1 https://github.com/0xNyk/awesome-agent-cortex
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 110 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00110
Opus 5 $0.00000 $0.00055
Sonnet 5 $0.00000 $0.00022
Haiku 4.5 $0.00000 $0.00011

Measured 2d ago against content hash 428dd8633dac, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

security scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

cursorrules/rules/security.mdc · 14 lines

What it actually says

  • Never commit secrets, API keys, or credentials
  • Validate and sanitize all external inputs
  • Use parameterized queries — never concatenate SQL
  • Escape output to prevent XSS
  • Use allowlists over blocklists
  • Pin dependencies and audit for vulnerabilities
  • Log security events but never log sensitive data
  • Use constant-time comparison for secrets/tokens
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 14 lines · 110 tokens per session scan A 428dd8633dac

Subscribe to this mod's changes

security is a cursor rule published in the GitHub repository 0xNyk/awesome-agent-cortex (211 stars, last pushed 5d ago), licensed CC0-1.0. It costs nothing until one of its globs matches a file; then it loads 110 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.