HCSEC-2026-34 - Consul vulnerable to an authorization bypass in the catalog node-write path

{
  "id": "896e4e924ed5e5bee16494c8f16d2a5292c6e5ab23c4273f1c23a193c9141fe7",
  "url": "https://discuss.hashicorp.com/t/hcsec-2026-34-consul-vulnerable-to-an-authorization-bypass-in-the-catalog-node-write-path/77736",
  "method": "llm",
  "payload": {
    "kind": "patch",
    "title": "HCSEC-2026-34 - Consul vulnerable to an authorization bypass in the catalog node-write path",
    "summary": "Consul and Consul Enterprise have an authorization bypass that may let an authenticated attacker with limited node-write access remove another node’s catalog registration and take over its identity. Upgrade to a listed fixed version.",
    "evidence": "Consul and Consul Enterprise are vulnerable to an authorization bypass in the catalog node-write path that may allow an authenticated attacker to delete another node’s catalog registration and take over its node identity.",
    "products": [
      {
        "name": {
          "value": "Consul",
          "evidence": "Consul and Consul Enterprise up to 2.0.3; fixed in Consul 2.0.4"
        },
        "prerequisites": [
          {
            "value": "a valid ACL token with node:write permission on at least one node, as well as knowledge of an identifier associated with a target node",
            "evidence": "Exploiting this issue requires a valid ACL token with node:write permission on at least one node, as well as knowledge of an identifier associated with a target node."
          }
        ],
        "fixed_versions": [
          {
            "value": "2.0.4",
            "evidence": "fixed in Consul 2.0.4"
          }
        ],
        "affected_versions": [
          {
            "value": "up to 2.0.3",
            "evidence": "Consul and Consul Enterprise up to 2.0.3; fixed in Consul 2.0.4"
          }
        ]
      },
      {
        "name": {
          "value": "Consul Enterprise",
          "evidence": "Consul and Consul Enterprise up to 2.0.3; fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12, and 2.0.4."
        },
        "prerequisites": [
          {
            "value": "a valid ACL token with node:write permission on at least one node, as well as knowledge of an identifier associated with a target node",
            "evidence": "Exploiting this issue requires a valid ACL token with node:write permission on at least one node, as well as knowledge of an identifier associated with a target node."
          }
        ],
        "fixed_versions": [
          {
            "value": "1.21.18",
            "evidence": "Consul Enterprise 1.21.18, 1.22.12, and 2.0.4."
          },
          {
            "value": "1.22.12",
            "evidence": "Consul Enterprise 1.21.18, 1.22.12, and 2.0.4."
          },
          {
            "value": "2.0.4",
            "evidence": "Consul Enterprise 1.21.18, 1.22.12, and 2.0.4."
          }
        ],
        "affected_versions": [
          {
            "value": "up to 2.0.3",
            "evidence": "Consul and Consul Enterprise up to 2.0.3; fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12, and 2.0.4."
          }
        ]
      }
    ],
    "severity": "unknown",
    "fixed_cves": [
      {
        "cve": "CVE-2026-87090",
        "product": "Consul",
        "evidence": "This vulnerability (CVE-2026-87090) is fixed in Consul 2.0.4"
      },
      {
        "cve": "CVE-2026-87090",
        "product": "Consul Enterprise",
        "evidence": "This vulnerability (CVE-2026-87090) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4."
      }
    ],
    "related_cves": [
      {
        "value": "CVE-2026-87090",
        "evidence": "This vulnerability (CVE-2026-87090) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4."
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "official-hashicorp-discuss-security",
  "document_id": 24008,
  "published_at": "2026-09-10T18:45:04+00:00"
}