Rybbit Reflects Any Origin in CORS Responses While Allowing Credentials

{
  "id": "80ad6d02b894055a598b35524e6e7c189ff68587768e0ef1cece3aaa5f7e2948",
  "url": "https://osv.dev/vulnerability/CVE-2026-82287",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Rybbit Reflects Any Origin in CORS Responses While Allowing Credentials",
    "summary": "Rybbit before 2.7.0 contains a CORS misconfiguration vulnerability that allows attackers to bypass origin restrictions by reflecting any request origin in Access-Control-Allow-Origin responses while credentials are enabled. Attackers can issue credentialed cross-origin requests from any website to read analytics data, account information, and perform authenticated state-changing operations as the victim user.",
    "evidence": "osv:CVE-2026-82287",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-82287",
      "aliases": [
        "CVE-2026-82287"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/rybbit-io/rybbit",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "17392d73df4e9aa19a2486446921cfd307041dec"
                },
                {
                  "fixed": "6f1039bdd3328a84d6700031bc0ce4714020e2f9"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.7.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "fixed": "6f1039bdd3328a84d6700031bc0ce4714020e2f9"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.6.1",
            "v2.6.0",
            "v2.5.0",
            "v2.4.0",
            "v2.3.1",
            "v2.3.0",
            "v2.2.4",
            "v2.2.3",
            "v2.2.2",
            "v2.2.1",
            "v2.2.0",
            "v2.1.1",
            "v2.0.1",
            "v2.0.0",
            "v1.7.0",
            "v1.6.1",
            "v1.6.0",
            "v1.5.1",
            "v1.5.0",
            "v1.4.1",
            "v1.4.0",
            "v1.3.0",
            "v1.2.0",
            "v1.1.0",
            "v1.0.0",
            "v0.4.2",
            "v0.4.1",
            "v0.4.0",
            "v0.3.1",
            "v0.3.0",
            "v0.2.0",
            "v0.1.4",
            "v0.1.3",
            "v0.1.2",
            "v0.1.1",
            "v0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-82287.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.838521706Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82287.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-82287",
        "https://www.vulncheck.com/advisories/rybbit-reflects-any-origin-in-cors-responses-while-allowing-credentials",
        "https://github.com/rybbit-io/rybbit/issues/1038",
        "https://github.com/rybbit-io/rybbit/commit/6f1039bdd3328a84d6700031bc0ce4714020e2f9",
        "https://github.com/rybbit-io/rybbit",
        "https://github.com/rybbit-io/rybbit/blob/v2.6.0/server/src/index.ts"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-942"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82287.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-82287",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 500051,
  "published_at": "2026-08-28T16:19:05.231+00:00"
}