guzzlehttp/psr7: Host Confusion via Weak URI Host Validation

{
  "id": "713315a45de0f75cfc2b2315efd36de940bdfe0552e98f7c52d2d97322633c95",
  "url": "https://osv.dev/vulnerability/CVE-2026-59882",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "guzzlehttp/psr7: Host Confusion via Weak URI Host Validation",
    "summary": "guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.3, Uri::assertValidHost() does not reject URI host components containing authority delimiters, embedded ports, or malformed IPv6 brackets, allowing Uri::getHost() to disagree with the URI authority used for security or routing decisions. This issue is fixed in version 2.12.3.",
    "evidence": "osv:CVE-2026-59882",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-59882",
      "aliases": [
        "CVE-2026-59882",
        "GHSA-c2w2-prh8-qm98"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/guzzle/psr7",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "7ec62dc3f44aa218487dbed81a9bf9bc647be55d"
                },
                {
                  "fixed": "ddd64f17d4cc1f7e5ffe6fd2c989ec7221712580"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:guzzlephp:psr-7:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.12.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ddd64f17d4cc1f7e5ffe6fd2c989ec7221712580"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "7ec62dc3f44aa218487dbed81a9bf9bc647be55d"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "2.12.3"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.12.2",
            "2.12.1",
            "2.12.0",
            "2.11.1",
            "2.11.0",
            "2.10.1",
            "2.10.0",
            "2.9.0",
            "2.8.1",
            "2.8.0",
            "2.7.1",
            "2.7.0",
            "2.6.3",
            "2.6.2",
            "2.6.1",
            "2.6.0",
            "2.5.0",
            "2.4.4",
            "2.4.3",
            "2.4.2",
            "2.4.1",
            "2.4.0",
            "2.3.0",
            "2.2.2",
            "2.2.1",
            "2.2.0",
            "2.1.0",
            "2.0.0",
            "2.0.0-rc1",
            "2.0.0-beta1",
            "1.6.0",
            "1.5.0",
            "1.5.2",
            "1.5.1",
            "1.4.2",
            "1.4.1",
            "1.4.0",
            "1.3.1",
            "1.3.0",
            "1.2.3",
            "1.2.2",
            "1.2.1",
            "1.2.0",
            "1.1.0",
            "1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59882.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:36.636481338Z",
      "provider": "osv",
      "references": [
        "https://github.com/guzzle/psr7/releases/tag/2.12.3",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59882.json",
        "https://github.com/guzzle/psr7/security/advisories/GHSA-c2w2-prh8-qm98",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-59882",
        "https://github.com/guzzle/psr7/commit/ddd64f17d4cc1f7e5ffe6fd2c989ec7221712580",
        "https://github.com/guzzle/psr7/pull/811"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-436"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59882.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-59882",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 503979,
  "published_at": "2026-07-08T15:50:03.077+00:00"
}