CVE-2026-23517: Github.com/fleetdm/fleet Fleet Has An Access Control Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4r5r-ccr6-q6f6",
  "modified" : "2026-02-27T22:03:20Z",
  "published" : "2026-01-20T20:55:14Z",
  "aliases" : [ "CVE-2026-23517" ],
  "summary" : "Fleet has an Access Control vulnerability in debug/pprof endpoints",
  "details" : "### Summary\n\nA broken access control issue in Fleet allowed authenticated users to access debug and profiling endpoints regardless of role. As a result, low-privilege users could view internal server diagnostics and trigger resource-intensive profiling operations.\n\n### Impact\n\nFleet’s debug/pprof endpoints are accessible to any authenticated user regardless of role, including the lowest-privilege “Observer” role. This allows low-privilege users to access sensitive server internals, including runtime profiling data and in-memory application state, and to trigger CPU-intensive profiling operations that could lead to denial of service.\n\n### Patches\n\n- 4.78.3\n- 4.77.1\n- 4.76.2\n- 4.75.2\n- 4.53.3\n\n### Workarounds\n\nIf an immediate upgrade is not possible, users should put the debug/pprof endpoints behind an IP allowlist. \n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\nEmail us at [security@fleetdm.com](mailto:security@fleetdm.com)\nJoin #fleet in [osquery Slack](https://join.slack.com/t/osquery/shared_invite/zt-h29zm0gk-s2DBtGUTW4CFel0f0IjTEw)\n\n### Credits\n\nWe thank @secfox-ai for responsibly reporting this issue.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.78.0"
      }, {
        "fixed" : "4.78.3"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.77.0"
      }, {
        "fixed" : "4.77.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.76.0"
      }, {
        "fixed" : "4.76.2"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.75.0"
      }, {
        "fixed" : "4.75.2"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet/v4"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.78.3-0.20260112221730-5c030e32a3a9"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/fleetdm/fleet/security/advisories/GHSA-4r5r-ccr6-q6f6"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-23517"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/fleetdm/fleet/commit/5c030e32a3a9bc512355b5e1bf19636e4e6d0317"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/fleetdm/fleet"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2026-4334"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-862", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-01-20T20:55:14Z",
    "nvd_published_at" : "2026-01-21T22:15:49Z"
  }
}