> ## Documentation Index
> Fetch the complete documentation index at: https://docs.endorlabs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Package Firewall

> Block known malicious packages and control package installations in real time with Endor Labs Package Firewall.

export const YamlTable = ({children, data: propData, content}) => {
  const KV_RE = /^([A-Za-z][A-Za-z0-9_()/#\s-]+?):\s*(.+)$/;
  const INLINE_MD_RE = /(\[([^\]]+)\]\(([^)]+)\))|(`([^`]+)`)|(\*\*([^*]+)\*\*)|(\*([^*]+)\*)/g;
  const YES_RE = /^-yes-$/i;
  const NO_RE = /^-no-$/i;
  const LIMITED_RE = /^-(limited|partial)-$/i;
  const NA_RE = /^-(na|none)-$/i;
  const NA2_RE = /^-na2-$/i;
  const SIMPLE_TAG_RE = /(<br\s*\/?>)|(<p\s*\/?>)|(-note-)|(-warning-)/gi;
  const renderSuccessIcon = () => <svg viewBox="0 0 24 24" width="100%" height="100%" aria-hidden="true">
      <path d="M12 2C6.48 2 2 6.48 2 12C2 17.52 6.48 22 12 22C17.52 22 22 17.52 22 12C22 6.48 17.52 2 12 2ZM10 17L5 12L6.41 10.59L10 14.17L17.59 6.58L19 8L10 17Z" fill="currentColor" />
    </svg>;
  const renderFailureIcon = () => <svg viewBox="0 0 24 24" width="100%" height="100%" aria-hidden="true">
      <path fillRule="evenodd" clipRule="evenodd" d="M11.9902 1.98633C12.5208 1.9864 13.0426 2.12743 13.501 2.39453C13.9581 2.66107 14.3372 3.04388 14.5986 3.50391L22.5967 17.5L22.6895 17.6738C22.8921 18.0851 22.9979 18.5387 22.9981 18.999C22.9981 19.5253 22.8605 20.0431 22.5977 20.499C22.3348 20.9549 21.9555 21.3332 21.5 21.5967C21.0445 21.8601 20.5272 21.9994 20.001 22H4.00001C3.47453 22.0031 2.95699 21.868 2.50001 21.6084C2.04032 21.3471 1.65712 20.9684 1.39063 20.5117C1.12431 20.055 0.983643 19.5355 0.982429 19.0068C0.981281 18.4793 1.11967 17.9611 1.38282 17.5039L9.38184 3.50391C9.64344 3.04359 10.023 2.66111 10.4805 2.39453C10.9388 2.12755 11.4598 1.98636 11.9902 1.98633ZM12 16.9004C11.3925 16.9004 10.9004 17.3925 10.9004 18C10.9004 18.6075 11.3925 19.0996 12 19.0996H12.0098C12.6173 19.0996 13.1104 18.6075 13.1104 18C13.1104 17.3925 12.6173 16.9004 12.0098 16.9004H12ZM12 5.90039C11.3925 5.9004 10.9004 6.39249 10.9004 7V13C10.9004 13.6075 11.3925 14.0996 12 14.0996C12.6075 14.0996 13.0996 13.6075 13.0996 13V7C13.0996 6.39249 12.6075 5.90039 12 5.90039Z" fill="currentColor" />
    </svg>;
  const renderPartialSuccessIcon = () => <svg viewBox="0 0 24 24" width="100%" height="100%" aria-hidden="true">
      <path d="M12 1C18.0751 1 23 5.92487 23 12C23 18.0751 18.0751 23 12 23C5.92487 23 1 18.0751 1 12C1 5.92487 5.92487 1 12 1ZM12 3C7.02944 3 3 7.02944 3 12C3 16.9706 7.02944 21 12 21C16.9706 21 21 16.9706 21 12C21 7.02944 16.9706 3 12 3ZM12 5C13.8565 5 15.6374 5.73705 16.9502 7.0498C18.263 8.36256 19 10.1435 19 12C19 13.8565 18.263 15.6374 16.9502 16.9502C15.6374 18.263 13.8565 19 12 19C11.4477 19 11 18.5523 11 18V6C11 5.73478 11.1054 5.4805 11.293 5.29297C11.4805 5.10543 11.7348 5 12 5Z" fill="currentColor" />
    </svg>;
  const renderPendingIcon = () => <svg viewBox="0 0 24 24" width="100%" height="100%" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" aria-hidden="true">
      <path d="M10.1 2.182a10 10 0 0 1 3.8 0" />
      <path d="M13.9 21.818a10 10 0 0 1-3.8 0" />
      <path d="M17.609 3.721a10 10 0 0 1 2.69 2.7" />
      <path d="M2.182 13.9a10 10 0 0 1 0-3.8" />
      <path d="M20.279 17.609a10 10 0 0 1-2.7 2.69" />
      <path d="M21.818 10.1a10 10 0 0 1 0 3.8" />
      <path d="M3.721 6.391a10 10 0 0 1 2.7-2.69" />
      <path d="M6.391 20.279a10 10 0 0 1-2.69-2.7" />
    </svg>;
  const renderRunningIcon = () => <svg className="yt-status-running-svg" viewBox="22 22 44 44" width="100%" height="100%" aria-hidden="true">
      <circle className="yt-status-running-circle" cx="44" cy="44" r="20.2" fill="none" stroke="currentColor" strokeWidth="3.6" />
    </svg>;
  const renderSkippedIcon = () => <svg viewBox="0 0 24 24" width="100%" height="100%" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
      <circle cx="12" cy="12" r="10" />
      <path d="M8 12h8" />
    </svg>;
  const STATUS_ICON_DEFS = [{
    re: /^-status-success-$/i,
    colorClass: 'yt-status-color-success',
    label: 'Success',
    render: renderSuccessIcon
  }, {
    re: /^-status-failure-$/i,
    colorClass: 'yt-status-color-failure',
    label: 'Failure',
    render: renderFailureIcon
  }, {
    re: /^-status-partial-success-$/i,
    colorClass: 'yt-status-color-partial',
    label: 'Partial success',
    render: renderPartialSuccessIcon
  }, {
    re: /^-status-pending-$/i,
    colorClass: 'yt-status-color-neutral',
    label: 'Pending',
    render: renderPendingIcon
  }, {
    re: /^-status-running-$/i,
    colorClass: 'yt-status-color-neutral',
    label: 'Running',
    render: renderRunningIcon
  }, {
    re: /^-status-skipped-$/i,
    colorClass: 'yt-status-color-neutral',
    label: 'Skipped',
    render: renderSkippedIcon
  }];
  const renderStatusBadge = def => <span className={['yt-status-icon', def.colorClass].join(' ')} role="img" aria-label={def.label} title={def.label}>
      {def.render()}
    </span>;
  const tryParseKV = trimmed => {
    const m = KV_RE.exec(trimmed);
    return m ? {
      key: m[1],
      value: m[2].trim()
    } : null;
  };
  const registerKey = (key, seenKeys, orderedKeys) => {
    if (!seenKeys.has(key)) {
      orderedKeys.push(key);
      seenKeys.add(key);
    }
  };
  const flushEntry = (currentEntry, entries) => {
    if (Object.keys(currentEntry).length > 0) entries.push(currentEntry);
  };
  const parseDashPrefixed = (lines, entries, orderedKeys, seenKeys) => {
    let currentEntry = {};
    let inEntry = false;
    for (const line of lines) {
      const trimmed = line.trim();
      if (trimmed.startsWith('- ')) {
        if (inEntry) entries.push(currentEntry);
        currentEntry = {};
        inEntry = true;
        const kv = tryParseKV(trimmed.substring(2).trim());
        if (kv) {
          registerKey(kv.key, seenKeys, orderedKeys);
          currentEntry[kv.key] = kv.value;
        }
      } else if (inEntry && trimmed !== '') {
        const kv = tryParseKV(trimmed);
        if (kv) {
          registerKey(kv.key, seenKeys, orderedKeys);
          currentEntry[kv.key] = kv.value;
        }
      }
    }
    flushEntry(currentEntry, entries);
  };
  const parseBlankSeparated = (lines, entries, orderedKeys, seenKeys) => {
    let currentEntry = {};
    let inEntry = false;
    for (const line of lines) {
      const trimmed = line.trim();
      if (trimmed === '') {
        if (inEntry) {
          flushEntry(currentEntry, entries);
          currentEntry = {};
          inEntry = false;
        }
        continue;
      }
      const kv = tryParseKV(trimmed);
      if (!kv) continue;
      const isNewEntry = !line.startsWith(' ') && !line.startsWith('\t');
      if (isNewEntry && inEntry && Object.keys(currentEntry).length > 0) {
        entries.push(currentEntry);
        currentEntry = {};
      }
      registerKey(kv.key, seenKeys, orderedKeys);
      currentEntry[kv.key] = kv.value;
      inEntry = true;
    }
    flushEntry(currentEntry, entries);
  };
  const normalizeEntries = (entries, orderedKeys) => entries.map(entry => {
    const filled = {};
    for (const key of orderedKeys) filled[key] = entry[key] || '';
    return filled;
  });
  const parseYamlTableContent = contentStr => {
    if (!contentStr) return [];
    const entries = [];
    const orderedKeys = [];
    const seenKeys = new Set();
    const lines = contentStr.split('\n');
    if (lines.some(line => line.trim().startsWith('- '))) {
      parseDashPrefixed(lines, entries, orderedKeys, seenKeys);
    } else {
      parseBlankSeparated(lines, entries, orderedKeys, seenKeys);
    }
    return normalizeEntries(entries, orderedKeys);
  };
  const processText = text => {
    if (!text) return text;
    const parts = [];
    let keyIndex = 0;
    let lastIndex = 0;
    let match;
    while ((match = INLINE_MD_RE.exec(text)) !== null) {
      if (match.index > lastIndex) parts.push(text.slice(lastIndex, match.index));
      if (match[1]) {
        parts.push(<a key={keyIndex++} href={match[3]}>{match[2]}</a>);
      } else if (match[4]) {
        parts.push(<code key={keyIndex++}>{match[5]}</code>);
      } else if (match[6]) {
        parts.push(<strong key={keyIndex++}>{match[7]}</strong>);
      } else if (match[8]) {
        parts.push(<em key={keyIndex++}>{match[9]}</em>);
      }
      lastIndex = match.index + match[0].length;
    }
    if (lastIndex < text.length) parts.push(text.slice(lastIndex));
    if (parts.length === 0) return text;
    const keyRef = {
      current: keyIndex
    };
    return expandHtmlTags(parts, keyRef);
  };
  const processBadges = text => {
    if (!text || typeof text !== 'string') return text;
    if (YES_RE.test(text)) return <span className="yt-badge-yes" role="img" aria-label="Supported" title="Supported">✓</span>;
    if (NO_RE.test(text)) return <span className="yt-badge-no" role="img" aria-label="Not supported" title="Not supported">✗</span>;
    if (LIMITED_RE.test(text)) return <span className="yt-badge-limited" role="img" aria-label="Partially supported" title="Partially supported">◐</span>;
    if (NA_RE.test(text) || NA2_RE.test(text)) return <span className="yt-sr-only" title="Not applicable">Not applicable</span>;
    const statusBadge = STATUS_ICON_DEFS.find(def => def.re.test(text));
    if (statusBadge) return renderStatusBadge(statusBadge);
    return processText(text);
  };
  const cellClassName = text => {
    if (!text || typeof text !== 'string') return undefined;
    if (NA_RE.test(text)) return 'yt-cell-na';
    if (NA2_RE.test(text)) return 'yt-cell-na2';
    return undefined;
  };
  const expandSimpleTags = (str, keyRef) => {
    const result = [];
    let last = 0;
    SIMPLE_TAG_RE.lastIndex = 0;
    let m;
    while ((m = SIMPLE_TAG_RE.exec(str)) !== null) {
      if (m.index > last) result.push(str.slice(last, m.index));
      if (m[1]) {
        result.push(<br key={keyRef.current++} />);
      } else if (m[2]) {
        result.push(<br key={keyRef.current++} />, <br key={keyRef.current++} />);
      } else if (m[3]) {
        result.push(<span key={keyRef.current++} className="yt-badge-note" style={{
          fontWeight: 600
        }}>Note: </span>);
      } else if (m[4]) {
        result.push(<span key={keyRef.current++} className="yt-badge-warning" style={{
          fontWeight: 600
        }}>Warning: </span>);
      }
      last = m.index + m[0].length;
    }
    if (last < str.length) result.push(str.slice(last));
    return result;
  };
  const expandHtmlTags = (chunks, keyRef) => {
    const out = [];
    for (const chunk of chunks) {
      if (typeof chunk === 'string') {
        out.push(...expandSimpleTags(chunk, keyRef));
      } else {
        out.push(chunk);
      }
    }
    return out;
  };
  const extractText = node => {
    if (node === null || node === undefined) return '';
    if (typeof node === 'string') return node;
    if (typeof node === 'number') return String(node);
    if (typeof node === 'boolean') return '';
    if (Array.isArray(node)) return node.map(extractText).join('');
    if (node && typeof node === 'object' && node.type) {
      const props = node.props || ({});
      if (typeof props.children === 'string') return props.children;
      if (props.children) return extractText(props.children);
      return '';
    }
    return String(node || '');
  };
  const [mounted, setMounted] = useState(false);
  const scrollWrapRef = useRef(null);
  const [isScrollable, setIsScrollable] = useState(false);
  useEffect(() => {
    setMounted(true);
  }, []);
  const data = useMemo(() => {
    if (propData) return propData;
    if (content && typeof content === 'string') return parseYamlTableContent(content);
    if (!children) return [];
    if (typeof children === 'string') return parseYamlTableContent(children);
    const childrenArray = Array.isArray(children) ? children : [children];
    return parseYamlTableContent(childrenArray.map(extractText).join('').trim());
  }, [children, propData, content]);
  const columns = useMemo(() => {
    if (!data || data.length === 0) return [];
    const firstRow = data[0];
    if (!firstRow || typeof firstRow !== 'object') return [];
    return Object.keys(firstRow);
  }, [data]);
  useEffect(() => {
    const wrap = scrollWrapRef.current;
    if (!wrap) return undefined;
    const updateScrollable = () => {
      setIsScrollable(wrap.scrollWidth > wrap.clientWidth);
    };
    updateScrollable();
    const observer = new ResizeObserver(updateScrollable);
    observer.observe(wrap);
    return () => observer.disconnect();
  }, [mounted, data]);
  if (!mounted) return null;
  if (!data || data.length === 0) return null;
  const rowKey = row => columns.map(c => row[c] || '').join('|');
  return <div ref={scrollWrapRef} style={{
    overflowX: 'auto',
    margin: '1.75rem 0'
  }} role={isScrollable ? 'region' : undefined} aria-label={isScrollable ? 'Scrollable table' : undefined} tabIndex={isScrollable ? 0 : undefined}>
      <table style={{
    display: 'table',
    width: '100%',
    minWidth: '100%',
    margin: 0
  }}>
        <thead>
          <tr>
            {columns.map(col => <th key={col}>{col.replaceAll('_', ' ')}</th>)}
          </tr>
        </thead>
        <tbody>
          {data.map(row => <tr key={rowKey(row)}>
              {columns.map(col => <td key={col} className={cellClassName(row[col])}>{processBadges(row[col])}</td>)}
            </tr>)}
        </tbody>
      </table>
    </div>;
};

export const LicenseBadge = ({sku, skus, relation = 'any'}) => {
  const DATA_URL = '/snippets/license-sku-data.json';
  const CACHE_KEY = 'license-sku-data';
  const CACHE_TTL_MS = 60 * 60 * 1000;
  const REGISTRY_KEY = '__licenseSkuRegistry';
  const FALLBACK_LICENSES_URL = '/introduction/licenses';
  const ACCENT = '#26D07C';
  const CONJUNCTION = {
    any: 'or',
    all: 'and'
  };
  const FONT_STACK = '-apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif';
  const [isDark, setIsDark] = useState(false);
  const [data, setData] = useState(null);
  const [hasFetchError, setHasFetchError] = useState(false);
  const skuList = useMemo(() => {
    if (Array.isArray(skus) && skus.length > 0) {
      return skus.filter(code => typeof code === 'string' && code.trim()).map(c => c.trim());
    }
    if (typeof sku === 'string' && sku.trim()) {
      return [sku.trim()];
    }
    return [];
  }, [sku, skus]);
  useEffect(() => {
    const check = () => {
      const root = document.documentElement;
      setIsDark(root.dataset.theme === 'dark' || root.classList.contains('dark'));
    };
    check();
    const observer = new MutationObserver(check);
    observer.observe(document.documentElement, {
      attributes: true,
      attributeFilter: ['data-theme', 'class']
    });
    return () => observer.disconnect();
  }, []);
  useEffect(() => {
    let cancelled = false;
    const readCache = () => {
      try {
        const raw = sessionStorage.getItem(CACHE_KEY);
        if (!raw) return null;
        const parsed = JSON.parse(raw);
        if (Date.now() - parsed.ts > CACHE_TTL_MS) {
          sessionStorage.removeItem(CACHE_KEY);
          return null;
        }
        return parsed.data;
      } catch (e) {
        return null;
      }
    };
    const writeCache = value => {
      try {
        sessionStorage.setItem(CACHE_KEY, JSON.stringify({
          ts: Date.now(),
          data: value
        }));
      } catch (e) {}
    };
    const fetchSkuData = async () => {
      const cached = readCache();
      if (cached) return cached;
      if (!globalThis[REGISTRY_KEY]) {
        globalThis[REGISTRY_KEY] = {};
      }
      const registry = globalThis[REGISTRY_KEY];
      if (registry[CACHE_KEY]) return registry[CACHE_KEY];
      const promise = (async () => {
        const resp = await fetch(DATA_URL);
        if (!resp.ok) throw new Error(`HTTP ${resp.status}`);
        const json = await resp.json();
        writeCache(json);
        return json;
      })();
      registry[CACHE_KEY] = promise;
      promise.finally(() => {
        delete registry[CACHE_KEY];
      });
      return promise;
    };
    fetchSkuData().then(d => {
      if (!cancelled) setData(d);
    }).catch(() => {
      if (!cancelled) setHasFetchError(true);
    });
    return () => {
      cancelled = true;
    };
  }, []);
  const textColor = isDark ? '#e6edf3' : '#1f2937';
  const textMuted = isDark ? 'rgba(230,237,243,0.65)' : 'rgba(31,41,55,0.65)';
  const bannerBackground = isDark ? '#161b22' : '#f6f8fa';
  const borderColor = isDark ? 'rgba(38,208,124,0.35)' : 'rgba(38,208,124,0.45)';
  const linkColor = isDark ? '#4ade80' : '#047857';
  const errorBackground = isDark ? '#3b1111' : '#fef2f2';
  const errorBorder = isDark ? '#7f1d1d' : '#fecaca';
  const errorText = isDark ? '#fecaca' : '#7f1d1d';
  const licensesUrl = data?.licensesPageUrl || FALLBACK_LICENSES_URL;
  const resolveSkuName = code => {
    const entry = data?.skus?.[code];
    if (entry?.name) return entry.name;
    return null;
  };
  const formatSkuLabel = code => {
    const name = resolveSkuName(code);
    if (name) return name;
    return code;
  };
  const joinWithConjunction = (codes, conjunction) => {
    const labels = codes.map(formatSkuLabel);
    if (labels.length === 0) return '';
    if (labels.length === 1) return labels[0];
    if (labels.length === 2) return `${labels[0]} ${conjunction} ${labels[1]}`;
    const head = labels.slice(0, -1).join(', ');
    const tail = labels[labels.length - 1];
    return `${head}, ${conjunction} ${tail}`;
  };
  const buildSkuSentence = codes => {
    const conj = CONJUNCTION[relation] || CONJUNCTION.any;
    const names = joinWithConjunction(codes, conj);
    const noun = codes.length > 1 ? 'licenses' : 'license';
    return `${names} ${noun}`;
  };
  const renderLink = text => <a href={licensesUrl} className="lic-link" style={{
    color: linkColor,
    fontSize: '0.75rem',
    fontWeight: 500,
    textDecoration: 'none',
    whiteSpace: 'nowrap'
  }}>
      {text} →
    </a>;
  const renderBanner = codes => <div className="lic-banner not-prose" style={{
    margin: '1rem 0',
    padding: '0.5rem 0.85rem',
    background: bannerBackground,
    border: `1px solid ${borderColor}`,
    borderLeft: `3px solid ${ACCENT}`,
    borderRadius: '6px',
    color: textColor,
    fontSize: '0.75rem',
    display: 'flex',
    alignItems: 'center',
    gap: '0.5rem',
    flexWrap: 'wrap',
    fontFamily: FONT_STACK,
    lineHeight: 1.5
  }}>
      <span style={{
    flex: 1,
    minWidth: 0
  }}>
        <span style={{
    color: textMuted,
    marginRight: '0.3rem'
  }}>Requires</span>
        <span style={{
    fontWeight: 600
  }}>{buildSkuSentence(codes)}</span>
      </span>
      {renderLink('Licenses')}
    </div>;
  const renderLoading = () => <div className="not-prose" style={{
    margin: '1rem 0',
    padding: '0.6rem 0.9rem',
    background: bannerBackground,
    border: `1px dashed ${borderColor}`,
    borderRadius: '6px',
    color: textMuted,
    fontSize: '0.85rem',
    fontStyle: 'italic',
    fontFamily: FONT_STACK
  }} role="status" aria-live="polite">
      Loading license info…
    </div>;
  const renderInputError = message => <div className="not-prose" style={{
    margin: '1rem 0',
    padding: '0.6rem 0.9rem',
    background: errorBackground,
    border: `1px solid ${errorBorder}`,
    borderRadius: '6px',
    color: errorText,
    fontSize: '0.85rem',
    fontFamily: FONT_STACK
  }} role="alert">
      {message}
    </div>;
  if (typeof sku === 'string' && Array.isArray(skus)) {
    return renderInputError('LicenseBadge: pass either `sku` or `skus`, not both.');
  }
  if (skuList.length === 0) {
    return renderInputError('LicenseBadge: `sku` or `skus` is required.');
  }
  if (hasFetchError) return renderBanner(skuList);
  if (!data) return renderLoading();
  return renderBanner(skuList);
};

<LicenseBadge sku="EL-OSS-FWAL" />

Package Firewall offers real-time protection against malicious packages during software installations. It safeguards your software supply chain by preventing malicious packages from reaching your developers. Positioned between package manager clients and public registries, it blocks the installation of known malicious packages by default while allowing safe packages to install normally.

Security teams often discover malware only after it enters your environment, forcing reactive cleanup. Package Firewall closes this gap by intercepting every package installation request before it completes. It blocks any malicious package instantly and returns an error, so the package never reaches your environment. Legitimate packages pass through unchanged, keeping your developers productive and your pipeline secure.

Package Firewall checks every package in the dependency tree individually, including transitive dependencies. If it flags any dependency, the installation is blocked. Configured policies apply to transitive dependencies as well. See [How it works](#how-it-works) for more details.

## Get started

<Steps>
  <Step title="Route traffic through Package Firewall">
    Choose a [deployment model](/package-firewall/deployment-models) that matches how you install packages. Then set up [JFrog Artifactory](/package-firewall/jfrog-artifactory), [Google Artifact Registry](/package-firewall/google-artifact-registry), [Sonatype Nexus Repository](/package-firewall/sonatype-nexus-repository), [direct integration](/package-firewall/direct-integration), or [MDM deployment](/package-firewall/mdm-deployment).
  </Step>

  <Step title="Configure a Package Firewall policy">
    Define how the firewall responds to flagged packages: block, warn, or allow safe versions on malware and minimum package age, block or warn on vulnerabilities and restricted licenses, and set exceptions. You can also send Slack notifications when a package installation is blocked or warned. See [Package Firewall policy](/package-firewall/policy).
  </Step>

  <Step title="View results">
    Confirm the firewall blocks malware and review every recorded event. See [View Package Firewall logs](/package-firewall/logs).
  </Step>
</Steps>

## Supported ecosystems

The Package Firewall supports the following public registries and any package manager client that uses them.

<YamlTable>
  {`
    - Public_registry: npm
    Package_manager_clients: npm, pnpm, Yarn, Bun
    Direct_integration: -yes-
    JFrog_Artifactory: -yes-
    Google_Artifact_Registry: -yes-
    Sonatype_Nexus_Repository: -yes-

    - Public_registry: PyPI
    Package_manager_clients: pip, Poetry, uv
    Direct_integration: -yes-
    JFrog_Artifactory: -yes-
    Google_Artifact_Registry: -yes-
    Sonatype_Nexus_Repository: -yes-

    - Public_registry: Go
    Package_manager_clients: Go modules
    Direct_integration: -yes-
    JFrog_Artifactory: -yes-
    Google_Artifact_Registry: -no-
    Sonatype_Nexus_Repository: -yes-

    - Public_registry: Maven
    Package_manager_clients: Maven
    Direct_integration: -yes-
    JFrog_Artifactory: -yes-
    Google_Artifact_Registry: -yes-
    Sonatype_Nexus_Repository: -yes-
    `}
</YamlTable>

<Note>
  Google Artifact Registry does not support custom upstream URL for Go remote repositories, so you cannot route Go modules through the Package Firewall with this integration. To route Go modules through the Package Firewall, use [JFrog Artifactory](/package-firewall/jfrog-artifactory), [Sonatype Nexus Repository](/package-firewall/sonatype-nexus-repository), or [direct integration](/package-firewall/direct-integration).
</Note>

Package Firewall can also block malicious VS Code extension installations from the Microsoft Marketplace. This is deployed separately through MDM. See [VS Code extensions](/package-firewall/vscode-extensions).

## How it works

Package Firewall inspects each package request before the package is downloaded. The request routes through the firewall directly, or through a private package registry such as JFrog Artifactory, Google Artifact Registry, or Sonatype Nexus Repository. See [Choose a Package Firewall deployment model](/package-firewall/deployment-models) to compare the two models.

1. **Route traffic through Package Firewall**: Your package manager client or private package registry forwards each request to the firewall so that it evaluates every package before the download completes.

2. **Authenticate and control access**: Package Firewall verifies that each request presents an Endor Labs API key with the Package Firewall User role.

3. **Evaluate each package request**: For each request, Package Firewall parses the ecosystem, package name, and version, and checks it against the Endor Labs malware database. If you configure a [Package Firewall policy](/package-firewall/policy), the firewall also evaluates vulnerabilities, restricted licenses, and minimum package age. You can define exceptions that let specific packages bypass all checks, so critical builds and workflows continue uninterrupted.

4. **Take action**: Based on the malware check and policy conditions, Package Firewall takes the configured action on the request and records an event with the package, version, and reason. You can set each condition (malware, vulnerabilities, restricted licenses, and minimum package age) to one of the following responses:

   * **Warn**: Records the event and allows the package installation without interrupting your CI pipeline.
   * **Block**: Prevents the package installation entirely and returns an error.
   * **Allow safe versions only (curate)**: Removes the unsafe versions from the response so the package manager client installs a safe version instead. Available for the malware and minimum package age conditions on the npm and PyPI ecosystems. See [Allow safe versions](/package-firewall/policy#allow-safe-versions) to learn more.

   When a package passes all checks, the installation proceeds and no log is recorded.

5. **Record events in Package Firewall logs**: Package Firewall records the actions the firewall takes on package installation requests, which is helpful for debugging and compliance. The logs include details such as the package, version, time of the event, and the reason the firewall flagged the package. See [View Package Firewall logs](/package-firewall/logs) for more details.