CVE-2026-126401

{
  "etk_id": "ETK-2026-4373",
  "cve_id": "CVE-2026-126401",
  "display_id": "CVE-2026-126401",
  "ghsa_id": "GHSA-mjrh-3v6h-8g5p",
  "euvd_id": "EUVD-2026-125164",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Unauthenticated SAML XML memory-exhaustion denial of service in Fleet",
  "summary": "Fleet versions before 4.86.2 are affected when processing unsigned SAML responses through the SSO callback. An unauthenticated attacker can cause excessive memory consumption and crash the Fleet server; exposure requires the SSO callback endpoint to be reachable.",
  "mitigation": "Upgrade the fleet package to version 4.86.2 or later. Restrict access to the SSO callback endpoint until the upgrade is complete.",
  "vendor": "fleetdm",
  "product": "fleet",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        "< 4.86.2"
      ],
      "ecosystem": "go",
      "fixed_versions": [
        ">= 4.86.2"
      ],
      "package_name": "github.com/fleetdm/fleet",
      "purl": "pkg:golang/github.com/fleetdm/fleet"
    }
  ],
  "cwes": [
    407
  ],
  "cvss_score": 8.7,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
  "epss_score": null,
  "epss_percentile": null,
  "epss_asof": null,
  "automation": "deterministic",
  "check": true,
  "check_confidence_basis": "differential",
  "exploit": false,
  "pipeline_minutes": 34.261077066666665,
  "t0_at": "2026-11-13T09:35:47.679000+00:00",
  "signals": {
    "check": {
      "at": "2026-11-13T10:56:04.768934+00:00",
      "days": 0.055753355717592594,
      "is_lower_bound": false,
      "measured_at": "2026-11-13T09:35:47.679000+00:00",
      "url": null
    },
    "trigger_signal": {
      "at": "2026-11-13T09:35:47.679000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-11-13T09:35:47.679000+00:00",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-126401"
    }
  }
}