ETK-2026-4041Zero's internal tracking ID, independent of the CVE number.

{
  "etk_id": "ETK-2026-4041",
  "cve_id": null,
  "display_id": "ETK-2026-4041",
  "ghsa_id": "GHSA-q9xq-w3q4-p9jc",
  "euvd_id": null,
  "status": "published",
  "anchor_state": "awaiting_cve",
  "title": "Path normalization authorization bypass in Skipper OPA filter",
  "summary": "Skipper can route a request using a normalized path while passing a different path representation to an OPA authorization policy. An unauthenticated requester may bypass path-based access controls when OPA is enabled and a route uses `opaAuthorizeRequest` with policy logic that treats alternate path forms differently.",
  "mitigation": "Upgrade Skipper to v0.28.74. Until upgraded, normalize or reject non-canonical request paths before they reach Skipper and review OPA policies that authorize based on path patterns.",
  "vendor": "go",
  "product": "go:github.com/zalando/skipper",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 0.18.0, <= 0.28.73"
      ],
      "ecosystem": "go",
      "fixed_versions": [
        "v0.28.74"
      ],
      "package_name": "github.com/zalando/skipper",
      "purl": "pkg:golang/github.com/zalando/skipper"
    }
  ],
  "cwes": [
    41
  ],
  "cvss_score": 9.1,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
  "epss_score": null,
  "epss_percentile": null,
  "epss_asof": null,
  "automation": "contextual",
  "check": true,
  "check_confidence_basis": "assessed",
  "exploit": false,
  "pipeline_minutes": 13.551746033333334,
  "t0_at": null,
  "signals": {
    "check": {
      "at": "2026-11-10T09:32:17.917312+00:00",
      "days": -0.8844042311921296,
      "is_lower_bound": true,
      "measured_at": "2026-11-11T06:45:50.483552+00:00",
      "url": null
    },
    "public_poc": {
      "at": "2026-11-09T18:42:36+00:00",
      "days": -1.502250496377315,
      "is_lower_bound": true,
      "measured_at": "2026-11-11T06:45:50.483552+00:00",
      "url": "https://github.com/zalando/skipper/security/advisories/GHSA-q9xq-w3q4-p9jc"
    },
    "trigger_signal": {
      "at": "2026-11-09T18:42:36+00:00",
      "days": -1.502250496377315,
      "is_lower_bound": true,
      "measured_at": "2026-11-11T06:45:50.483552+00:00",
      "url": "https://github.com/zalando/skipper/security/advisories/GHSA-q9xq-w3q4-p9jc"
    }
  }
}