selvo

selvo

Know what's actually dangerous on your Linux servers.

selvo scans your installed packages, checks every CVE against 8 data sources, filters out what your distro already patched, and ranks the rest by blast radius and exploit probability. Not just a list — a prioritized action plan.

Primary interfaces are the CLI and the MCP server (for Claude Desktop, Cursor, and other agent clients). A daily public sample report runs at copelabs.dev/selvo-report/.

Note — hosted SaaS is archived. selvo previously shipped a hosted REST API. That surface has been retired and is preserved under archive/saas/ for revival if there's demand. selvo today is a local-use tool: pip install selvo and run the CLI or wire up the MCP server.

Quick Start

pip install selvo

Scan your own machine:

selvo analyze --context local --ecosystem all --limit 50

Or wire the MCP server into Claude Desktop / Cursor:

{
  "mcpServers": {
    "selvo": { "command": "selvo-mcp" }
  }
}

Then ask your agent "triage this box" or use the built-in /selvo:triage, /selvo:kev_check, /selvo:patch_safe slash commands.

What Makes It Different

Distro-aware CVE filtering. If Debian backported a fix into zlib 1.2.11, we don't flag it. We cross-reference the Debian Security Tracker to remove CVEs your distro already patched. Other scanners miss this and massively over-report.

Blast radius scoring. A CVE in a library that 200 packages depend on ranks higher than one in a leaf package. We build real dependency graphs from Debian Packages.gz, Alpine APKINDEX, and Arch repo DBs.

Exploit intelligence. CISA KEV status, public exploit availability, EPSS exploitation probability — not just CVSS severity.

Agent-native contract. The MCP server exposes 16 tools with formal output schemas, structured errors with error_code for deterministic branching, cache-first idempotency on the expensive analyze_packages call, tool annotations (readOnlyHint, idempotentHint) so MCP clients auto-approve safely, and streaming progress on first-run pipelines.

MCP Server (Agent Integration)

16 tools for Claude Desktop, Cursor, and any MCP-compatible client. Entry points:

Tool	Purpose
analyze_packages	Primary entry — cache-first, idempotent. Returns cached data when fresh, re-runs the 1–3 min pipeline only when stale or force_refresh=True.
check_local_risk	Audit the machine selvo is running on (dpkg/rpm/pacman/apk).
check_runtime_risk	Scan /proc/*/maps for CVE-affected libraries actually loaded in memory. Requires root for full coverage.
fleet_scan	Multi-machine SSH rollup with version-drift surfacing.
list_cves	Filter the snapshot by CVSS / EPSS / advisory presence.
check_exploits	KEV + weaponized/PoC filter.
patch_plan	Partitions into deploy_now (low regression risk) vs test_first.
distro_lag	Per-distro version-lag comparison; optional real patch dates.
describe_package	Full per-package detail from the snapshot.
Plus	get_sla_report, get_epss_velocity, get_upstream_watchlist, and more.

Every response carries staleness metadata (snapshot_age_hours, stale) and every error carries error_code + remediation.tool so agents can branch deterministically.

Prompts (slash commands)

• /selvo:triage — top 5 risks on this machine with patch guidance
• /selvo:kev_check — actively exploited CVEs (CISA KEV / weaponized)
• /selvo:patch_safe — what's safe to deploy today

Telemetry (opt-in, off by default)

The MCP server can emit anonymous per-tool-call events to help tune which tools agents actually use. Off by default — enable with:

export SELVO_TELEMETRY=1

Payload is minimum-data: install_id (random UUID at ~/.cache/selvo/install_id — delete to reset), tool_name, success, error_code, duration_ms, selvo_version, python_version, os_family, transport. No package names, no CVE IDs, no hostnames, no paths.

There is no default ingest URL — the hosted service that used to receive these events was retired. Point the client at your own ingest via SELVO_TELEMETRY_ENDPOINT=…; without it, enabling the flag is a no-op.

CLI

The full analysis pipeline runs locally without a hosted service:

selvo analyze --ecosystem debian --limit 50
selvo scan requirements.txt --output sarif --file results.sarif
selvo policy check                       # policy-as-code gate
selvo fix --dry-run --top 5              # preview upstream PR fixes
selvo fleet scan hosts.txt               # SSH multi-machine
sudo selvo runtime                       # loaded .so files in live processes
selvo compliance --framework fedramp
selvo sla
selvo trend
selvo diff

All commands operate on a local SQLite cache under ~/.cache/selvo/.

GitHub Action

Cope-Labs/selvo-action runs the selvo CLI on GitHub runners against the runner's own installed packages, posts results as a PR comment, and fails CI on CISA KEV / weaponized exploits. See the action's own README for current usage.

Scoring (0–100)

Signal	Weight	Source
Dependency blast radius	22%	Transitive reverse deps from package index
EPSS exploit probability	20%	FIRST.org
Chokepoint centrality	15%	Betweenness centrality via NetworkX
Version lag	14%	Repology upstream vs installed
CVSS severity	10%	NVD
Exploit maturity	8%	CISA KEV + PoC/weaponized detection
Ecosystem popularity	7%	Repology repo count
Download count	2%	popcon / Homebrew
Days exposed	2%	CVE disclosure date age

Packages with no security signal are capped at 20. Runtime-loaded packages with CVEs get a 1.5× multiplier.

Post-April-2026 NVD caveat: NIST stopped enriching the long tail of CVEs with CVSS scores (NIST NVD policy change). When a CVE lacks CVSS, selvo redistributes the 10% CVSS weight to EPSS (+7%) and exploit maturity (+3%) — the remaining severity signals that are available. Scores stay comparable across CVSS-scored and CVSS-unscored CVEs instead of silently compressing by 10 points.

Policy-as-Code

Define security gates in YAML and evaluate with selvo policy check:

version: 1
block:
  on_kev: true
  on_weaponized: true
  min_cvss: 9.0
  min_score: 80
warn:
  on_poc: true
  min_cvss: 7.0
sla:
  critical: 7
  high: 30
  medium: 90
  low: 365
allow:
  cves:
    - id: CVE-2023-12345
      reason: "Not reachable in our deployment"
      expires: 2025-12-31

The CLI auto-discovers selvo.policy.yml in the working directory.

Data Sources

Source	What it provides
OSV.dev	CVE-to-package mapping with version ranges
FIRST.org EPSS	Daily exploitation probability scores
NVD	CVSS v3 base scores
Debian Security Tracker	Which CVEs are already patched by your distro
CISA KEV	Known Exploited Vulnerabilities catalog
Repology	Upstream versions, cross-distro comparison
Ubuntu USN	Ubuntu advisory IDs
Fedora Bodhi	Fedora advisory IDs

Supported Ecosystems

Native OSV coverage (11): Debian, Ubuntu, Fedora, Alpine, Rocky Linux, AlmaLinux, SUSE, openSUSE, Wolfi, Chainguard, Mageia.

Via Debian namespace (5): Arch, NixOS, Homebrew, Chocolatey, Winget.

Plus: CycloneDX/SPDX SBOM, Grype/Trivy JSON, and 11 lockfile formats (requirements.txt, package-lock.json, Cargo.lock, go.sum, Gemfile.lock, composer.json, pom.xml, and more).

License

Elastic License 2.0 (ELv2) — free to use, modify, and self-host. You may not offer selvo as a managed service to third parties. For managed-service licensing, contact [e-mail].

Built by Cope Labs LLC.