@cyanheads/cisa-cybersecurity-mcp-server
CISA Known Exploited Vulnerabilities with BOD 26-04 deadlines, SSVC prioritization, and the full ICS advisory corpus (CSAF) via MCP. Keyless. STDIO or Streamable HTTP.
7 Tools • 2 Data Resources • 1 Skill
Overview
CISA's vulnerability data in one place: the Known Exploited Vulnerabilities catalog with its remediation deadlines, per-CVE SSVC decision points, ICS advisories back to 2010, and CISA's latest alerts. Check a scan's worth of CVEs against KEV in one call, find what's overdue for a vendor, and work out BOD 26-04 timelines. No API key required.
Tools
Resources
Both data resources are fully covered by the tools above. The CISA cybersecurity guide covers evidence gates, CVE-to-product investigation, and incomplete coverage. It ships with plugin, npm, Docker, and MCPB installs and is served at skill://cisa-cybersecurity-guide/SKILL.md through MCP skill discovery.
Capability reference
cisa_list_reference tool
- One required
topic: directives, kev_fields, ssvc_values, sectors, advisory_id_formats, severity_bands, or sources; reads in-process state only, so it answers while other tools are failing
directives adds timelineTable (all 16 rows of BOD 26-04 Table 1, with remediationTimelineDays and forensicTriageRequired), definitions, and supersedes; sources reports the KEV catalogVersion, the advisory index's ready / documentCount / syncStatus, the SSVC cache TTL, and the cached feed windows
cisa_check_cve_status tool
- Processes up to 200
cveIds per call from the cached KEV snapshot with no upstream request; inputs up to 1,000 IDs return normalized unprocessedIds for a follow-up call. A CVE outside KEV comes back inKev: false, not as an error
- Per CVE:
dateAdded, dueDate, daysUntilDue, overdue, requiredAction, knownRansomwareCampaignUse, forensicTriage, cwes[], every URL in the entry's notes as references[] typed by kind, and a three-state directive (BOD 26-04, BOD 22-01, or null); the response echoes the catalog snapshot and the asOf date the deadlines were computed against
detail: "summary" trims each in-KEV record to the triage fields (dates, deadline status, directive, vendor and product labels, ransomware and forensic-triage flags), which keeps a full 200-CVE batch compact; full is the default
cisa_search_kev tool
- Filters AND together:
vendorProject and product (CISA's own labels, not CPE names), nameContains, cwe, cveIdPrefix, dateAddedFrom / dateAddedTo, dueBefore / dueAfter, overdue, ransomware, forensicTriage, directive (BOD 26-04 / BOD 22-01 / none); up to 100 per page (default 25) with an opaque cursor; sorts by dateAdded (default) or dueDate
- Reports
totalCount and appliedFilters; each continued page uses the current call's limit. A zero-hit result names the filter responsible and what dropping it restores. nameContains searches a-z and 0-9 after folding case and accents, and the notice names any other characters it dropped
- Typed errors:
catalog_unavailable (retryable), invalid_date_range, empty_search_text
cisa_get_ssvc tool
- Processes up to 50
cveIds per call through the Vulnrichment cache, fetching uncached records; inputs up to 1,000 IDs return normalized unprocessedIds for a follow-up call. assetExposure: publicly_exposed, not_publicly_exposed, or unknown (default, returns both arms)
- Per CVE:
found, exploitation, automatable, technicalImpact, cvss and cwes where CISA published them, and bod2604.timelines[] (tableRow, remediationTimelineDays, forensicTriageRequired); a KEV entry adds kevAssigned, plus assignmentAgrees when an exposure was stated
- Each result carries
outcome: ssvc, not_found, no_cisa_container, no_ssvc_metric, or fetch_failed. foundCount, notFoundCount, and failedCount separate published SSVC, confirmed misses, and unavailable lookups; enrichment_source_unavailable (retryable) fires when every processed lookup fails
cisa_search_ics_advisories tool
- Full-text
q over titles, vendor names, and product names, plus vendor, product (case-insensitive substrings), cve, cwe, inKev, cvssMin / cvssMax, severity, sector, series (ICSA / ICSMA), publisher (coordinator / other), publishedFrom / publishedTo, revisedFrom / revisedTo; sorts by revised (default), published, maxCvss, or relevance (needs q); up to 50 per page (default 20) with an opaque cursor
- Results carry
advisoryId, up to 20 cves with cveCount, kevCves, maxCvss with severityDerived, sectors, url, csafUrl, and attribution, plus totalCount and appliedFilters; a zero-hit result names the filter responsible. If the KEV snapshot isn't loaded, kevCves is left out and says so
- Typed errors:
mirror_not_ready, mirror_busy, and catalog_unavailable (retryable), mirror_unavailable, invalid_cvss_range, invalid_date_range, relevance_sort_without_query, empty_search_text
cisa_get_advisory tool
advisoryId (optional revision suffix), optional sections (advisory, summary, products, vulnerabilities, revisionHistory, references, acknowledgments), cves to pick vulnerability entries, and productIds to pick exact, case-sensitive product definitions; cves and productIds imply their sections
- Returns
kind: "full", or kind: "outline" (per-section byte sizes plus the CVE IDs) when a read without sections exceeds 24,000 bytes; re-call with sections. Both arms retain advisory identity, source links, and attribution
- Vulnerability entries retain applicability
flags and threats; remediations, flags, and threats resolve referenced product groups into productIds and keep groupIds. Undefined groups remain visible without invented product definitions
- An ID not in the index returns
found: false with guidance, indexCheckpoint, and indexLastSyncedAt; the guidance notes when the advisory may be newer than the index
- Typed errors:
mirror_not_ready and mirror_busy (retryable), mirror_unavailable, unknown_section, unknown_cve, cves_need_vulnerabilities_section, unknown_product_id, product_ids_need_products_section
cisa_get_alerts tool
feed: advisories (default), alerts, or ics; default limit 30, the upstream window size; since (YYYY-MM-DD) filters within that window and cannot reach past it. hasMore and an opaque cursor continue after the last returned item within the same feed; an unavailable anchor returns an empty page with restart guidance
- Items carry
title, link, pubDate, summary (HTML stripped, capped at 1,200 characters, flagged by summaryTruncated), and on ICS items an advisoryId for cisa_get_advisory; window reports itemCount, oldest, newest, and upstreamWindowSize
- Every response carries
fetchedAt and stale; if a refresh fails, the last window is returned as stale with retry guidance, and a stale empty result doesn't prove nothing was published. With no cached window, feed_unavailable (retryable)
cisa://kev/{cveId} resource
- One KEV record as
application/json, the same shape as a cisa_check_cve_status result under the default detail: "full"; a CVE not in KEV is a not-found error
- Listing returns the 30 most recently added entries;
cveId completes from the snapshot, up to 100 suggestions
cisa://advisory/{advisoryId} resource
- One flattened advisory as
application/json, with the same 24,000-byte outline-on-overflow as cisa_get_advisory; the template takes no sections, cves, or productIds, so follow an outline up with the tool
- Listing returns the 30 most recently revised advisories;
advisoryId completes from the index, up to 100 suggestions
Features
Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.
CISA-specific:
- Four public sources, no account or key: the KEV JSON feed, Vulnrichment, the CSAF ICS advisory repository, and CISA's RSS feeds
- None of them offers search, so filters run locally: KEV from an in-memory snapshot polled for changes, ICS advisories from a SQLite index with FTS5. Date filters take real calendar dates in
YYYY-MM-DD
- A bad KEV refresh is rejected and the last valid snapshot stays in use; with none, reads return retryable
catalog_unavailable
- The KEV, SSVC, and alert tools serve from the first request while the advisory index seeds in the background
- BOD 26-04 Table 1 ships as data, so a computed timeline is a table lookup over published decision points. It is not a compliance determination, and it is reported beside CISA's KEV due date, never reconciled with it
Agent-friendly output:
- Provenance on every response: the KEV
catalog version and asOf date, the index checkpoint behind a search, and url, csafUrl, and attribution on every advisory
- Discriminated outputs: a three-state
directive, typed references[].kind, found / inKev booleans, severityDerived on a band upstream never published, and typed error reasons with recovery hints
- Empty results and upstream gaps explain themselves: a zero-hit search names the filter responsible, and filters that hit a known gap (sector notes only from 2017, CVSS v2-only advisories, no KEV revision timestamps) say so. See Known Limitations
Getting started
Public Hosted Instance
A public instance is available at https://cisa-cybersecurity.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP:
Self-Hosted / Local
Add the following to your MCP client configuration file. No API key is required.
Or with npx (no Bun required):
Or with Docker:
For Streamable HTTP, set the transport and start the server:
Prerequisites
- Bun v1.4.0 or higher (or Node.js v24+).
- No credentials. Every upstream source is keyless and public.
Installation
- Clone the repository:
- Navigate into the directory:
- Install dependencies:
Configuration
Every variable is optional; the server runs correctly with none of them set.
Oversized read limits are bounded to each tool's workload cap, with notices when matching rows are omitted. CVE batches return the unprocessed IDs explicitly. All five read inputs have a hard ceiling of 1,000; malformed IDs anywhere in a batch still reject the call. Set CISA_CLAMP_OVERSIZED_INPUTS=false to reject inputs above the per-call caps with read_limit_exceeded before upstream or index work. Each normalization emits a structured log and the mcp.cisa.input.normalized counter, keyed by tool and input.
See .env.example for the full list of optional overrides.
Running the server
Local development
-
Build and run:
-
Run checks and tests:
ICS advisory index
The two ICS tools and the advisory resource read a local SQLite index of the CSAF corpus at CISA_CSAF_MIRROR_PATH, defaulting to your user cache directory. On first run the server builds it in the background; until it is ready those surfaces return a retryable mirror_not_ready, and cisa_list_reference with topic sources shows progress. If the path cannot be opened, the ICS surfaces fail with a non-retryable mirror_unavailable and every other tool keeps working.
Processes sharing one index take turns syncing it. For containers, CI, or seeding out of band (CISA_CSAF_MIRROR_AUTO_INIT=false, and CISA_CSAF_REFRESH_CRON=off to leave refreshes to you), run the scripts directly:
A transient SQLite lock returns retryable mirror_busy; retry shortly. After a partial refresh, applied rows stay readable and failed documents are retried next time; sources reports syncStatus: partial and failedDocumentCount, and mirror:refresh and mirror:verify exit non-zero.
Docker
The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/cisa-cybersecurity-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them. The image sets CISA_CSAF_MIRROR_PATH=/usr/src/app/.mirror/csaf.sqlite3; mount a volume over /usr/src/app/.mirror so the advisory index survives a container recreation; the image ships the mirror:* scripts for docker exec <container> bun run mirror:refresh.
Project structure
Development guide
See CLAUDE.md/AGENTS.md for development guidelines and architectural rules, and docs/design.md for the as-built specification. The short version:
- Handlers throw, framework catches — no
try/catch in tool logic
- Use
ctx.log for request-scoped logging, ctx.state for tenant-scoped storage
- Register new tools and resources via the barrels in
src/mcp-server/*/definitions/index.ts
- Wrap external sources: validate raw → normalize to a domain type → return the output schema; never fabricate a field the upstream omitted
Contributing
Issues are welcome. Run checks and tests before submitting:
License
Apache-2.0 — see LICENSE for details.
The license covers this code, not the data it serves. KEV entries are US Government work in the public domain and Vulnrichment is CC0-1.0, but the CSAF repository declares no license and many advisories republish vendor text, so check reuse rights at each advisory's url before redistributing it. This project is not affiliated with or endorsed by CISA or the Department of Homeland Security.