Timing Side-Channel in Vault’s Userpass Auth Method

{
  "id": "c395686cda35ac5e23b854e2c520413dd7e1c0231ff4d36a7b6b17626e23dc0a",
  "url": "https://osv.dev/vulnerability/CVE-2025-6011",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Timing Side-Channel in Vault’s Userpass Auth Method",
    "summary": "A timing side channel in Vault and Vault Enterprise’s (“Vault”) userpass auth method allowed an attacker to distinguish between existing and non-existing users, and potentially enumerate valid usernames for Vault’s Userpass auth method. Fixed in Vault Community Edition 1.20.1 and Vault Enterprise 1.20.1, 1.19.7, 1.18.12, and 1.16.23.",
    "evidence": "osv:CVE-2025-6011",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2025-6011",
      "aliases": [
        "BIT-vault-2025-6011",
        "CVE-2025-6011",
        "GHSA-mwgr-84fv-3jh9",
        "GO-2025-3839"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/hashicorp/vault",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "b403b1a27c8db6038ffefb296d7be0962e08039d"
                },
                {
                  "introduced": "6fdd6b59e97d97a9e19b0fb5304bf879c190295e"
                },
                {
                  "last_affected": "6fdd6b59e97d97a9e19b0fb5304bf879c190295e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:hashicorp:vault:*:*:*:*:-:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.20.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:hashicorp:vault:1.20.0:*:*:*:enterprise:*:*:*",
                    "range": [
                      {
                        "introduced": "1.20.0"
                      },
                      {
                        "last_affected": "1.20.0"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.20.0",
            "v1.20.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-6011.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.595411668Z",
      "provider": "osv",
      "references": [
        "https://discuss.hashicorp.com/t/hcsec-2025-15-timing-side-channel-in-vault-s-userpass-auth-method/76034",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/6xxx/CVE-2025-6011.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-6011",
        "https://github.com/hashicorp/vault"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-203"
        ],
        "cna_assigner": "HashiCorp",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "1.19.7"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "ChangesAt"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/6xxx/CVE-2025-6011.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-6011",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504947,
  "published_at": "2025-08-01T18:00:24.528+00:00"
}