# security_fetch_cisa_kev

Check whether a CVE is in the CISA Known Exploited Vulnerabilities (KEV) catalog. Read-only. No side effects. Idempotent. cve_id: CVE identifier in format CVE-YYYY-NNNNN e.g. CVE-2021-44228. Required. Returns in_kev (bool), date_added, due_date, ransomware_use, and notes from the CISA KEV catalog. KEV status answers 'Is this being actively exploited?' — a critical triage question not available in NIST NVD. Verified source: CISA KEV catalog (updated daily, cached). Use security_fetch_cve_detail for full CVE severity. Use security_fetch_cve_epss for exploit probability. If this tool's response does not serve the user's need, call report_feedback with feedback_type="agent_gap", tool_id="security_fetch_cisa_kev", intended_query="{what the user needed}", gap_description="{what was missing or wrong in the result}".

Agent View of the PolicyLayer registry record for `security_fetch_cisa_kev`. HTML page: https://policylayer.com/tools/dev-7bd0-mcp-server/security-fetch-cisa-kev

## Facts

- Tool: `security_fetch_cisa_kev`
- Server: DataNexus MCP (`dev-7bd0/mcp-server`) — https://policylayer.com/tools/dev-7bd0-mcp-server.md
- Homepage: https://github.com/dev-7bd0/mcp-server
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 1
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `cve_id` | string | no | CVE identifier e.g. CVE-2021-44228. Required. |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "security_fetch_cisa_kev",
    "arguments": {}
  }
}
```

## Why security_fetch_cisa_kev is rated Low

This is a straightforward read operation that queries public security data from the CISA KEV catalog. It retrieves and returns information about known exploited vulnerabilities without creating, modifying, deleting, executing code, or committing financial obligations. The tool explicitly declares itself read-only and idempotent, confirming no side effects.

From the tool's own definition: "Tool description explicitly states 'Read-only. No side effects. Idempotent.' It 'Check[s] whether a CVE is in the CISA Known Exploited Vulnerabilities (KEV) catalog' and 'Returns in_kev (bool), date_added, due_date, ransomware_use, and notes' — pure data…"

## Use case

AI agents call security_fetch_cisa_kev to retrieve information from DataNexus MCP without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches DataNexus MCP:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "security_fetch_cisa_kev": {}
  }
}
```

## Other tools on DataNexus MCP (54)

- `apikeys_revoke_api_key` — Destructive — https://policylayer.com/tools/dev-7bd0-mcp-server/apikeys-revoke-api-key.md
- `apikeys_rotate_api_key` — Destructive — https://policylayer.com/tools/dev-7bd0-mcp-server/apikeys-rotate-api-key.md
- `compliance_check_sam_exclusion` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/compliance-check-sam-exclusion.md
- `compliance_fetch_finra_broker` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/compliance-fetch-finra-broker.md
- `compliance_fetch_npi_provider` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/compliance-fetch-npi-provider.md
- `compliance_search_npi_by_name` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/compliance-search-npi-by-name.md
- `domain_check_email_security` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-check-email-security.md
- `domain_fetch_dns_records` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-dns-records.md
- `domain_fetch_domain_history` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-domain-history.md
- `domain_fetch_domain_rdap` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-domain-rdap.md
- `domain_fetch_reverse_ip` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-reverse-ip.md
- `domain_fetch_ssl_certificate_chain` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-ssl-certificate-chain.md
- `domain_fetch_subdomains` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/domain-fetch-subdomains.md
- `frontend_security_audit_ci_pipeline` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/frontend-security-audit-ci-pipeline.md
- `frontend_security_audit_manifest` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/frontend-security-audit-manifest.md
- `frontend_security_detect_typosquatting` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/frontend-security-detect-typosquatting.md
- `frontend_security_fetch_package_risk_brief` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/frontend-security-fetch-package-risk-brief.md
- `govcon_fetch_open_solicitations` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/govcon-fetch-open-solicitations.md
- `govcon_fetch_vendor_contract_history` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/govcon-fetch-vendor-contract-history.md
- `govcon_search_contract_awards` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/govcon-search-contract-awards.md
- `legal_fetch_inventor_portfolio` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/legal-fetch-inventor-portfolio.md
- `legal_fetch_patent_by_number` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/legal-fetch-patent-by-number.md
- `legal_fetch_patent_citations` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/legal-fetch-patent-citations.md
- `legal_search_patents_by_keyword` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/legal-search-patents-by-keyword.md
- `nonprofit_fetch_charity_uk` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-fetch-charity-uk.md
- `nonprofit_fetch_nonprofit_by_ein` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-fetch-nonprofit-by-ein.md
- `nonprofit_fetch_nonprofit_financial_trends` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-fetch-nonprofit-financial-trends.md
- `nonprofit_fetch_nonprofit_full_profile` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-fetch-nonprofit-full-profile.md
- `nonprofit_search_nonprofits_by_category` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-search-nonprofits-by-category.md
- `nonprofit_search_nonprofits_by_name` — Read — https://policylayer.com/tools/dev-7bd0-mcp-server/nonprofit-search-nonprofits-by-name.md
- …and 24 more: https://policylayer.com/tools/dev-7bd0-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=dev-7bd0-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/dev-7bd0-mcp-server