ETK-2026-2558Zero's internal tracking ID, independent of the CVE number.

{
  "etk_id": "ETK-2026-2558",
  "cve_id": null,
  "display_id": "ETK-2026-2558",
  "ghsa_id": "GHSA-26q8-h657-pf84",
  "euvd_id": null,
  "status": "published",
  "anchor_state": "awaiting_cve",
  "title": "Compromised CA trust in Bun TLS certificate store",
  "summary": "Bun 1.4.3 and earlier can trust TLS certificate chains associated with compromised emSign certificate authority keys. An attacker able to intercept a Bun TLS connection could impersonate a server and read or alter traffic, including downloaded packages; compiled Bun executables remain affected until rebuilt. Connections using Bun's default trust store are exposed.",
  "mitigation": "Upgrade Bun to 1.4.4 and rebuild executables produced with `bun build --compile`. Until upgraded, configure an explicit per-connection or installation CA bundle that excludes the affected emSign roots.",
  "vendor": "npm",
  "product": "npm:bun",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        "< 1.4.4"
      ],
      "ecosystem": "npm",
      "fixed_versions": [
        "1.4.4"
      ],
      "package_name": "bun",
      "purl": "pkg:npm/bun"
    }
  ],
  "cwes": [
    295
  ],
  "cvss_score": 7,
  "cvss_src": "ethiack_provisional",
  "cvss_vector": null,
  "epss_score": null,
  "epss_percentile": null,
  "epss_asof": null,
  "automation": "deterministic",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 17.023813733333334,
  "t0_at": null,
  "signals": {
    "trigger_signal": {
      "at": "2026-10-23T02:02:06+00:00",
      "days": -1.8703102571990742,
      "is_lower_bound": true,
      "measured_at": "2026-10-24T22:55:20.848167+00:00",
      "url": "https://github.com/oven-sh/bun/security/advisories/GHSA-26q8-h657-pf84"
    }
  }
}