Forem vulnerable to bypass of email address domain restrictions

{
  "id": "5091c4dbe3dbcf0f26e494621b0fddb303f0d809b716d2203cae504de0c94deb",
  "url": "https://osv.dev/vulnerability/CVE-2026-48780",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Forem vulnerable to bypass of email address domain restrictions",
    "summary": "Forem is open source software for building communities. Prior to commit a2ab6d4, a maliciously crafted email address could allow an attacker to bypass domain allowlist or denylist restrictions and gain access to invite-only forem deployments. The issue is patched as of `a2ab6d4`. As a workaround, some SMTP servers and email delivery providers may drop or refuse to send maliciously crafted email addresses.",
    "evidence": "osv:CVE-2026-48780",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-48780",
      "aliases": [
        "CVE-2026-48780",
        "GHSA-3g4h-9h37-mpx6"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/forem/forem",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "a2ab6d4"
                },
                {
                  "fixed": "a2ab6d409d2676eb0711ecbd737192043125b437"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "a2ab6d4"
                      }
                    ],
                    "source": "DESCRIPTION"
                  },
                  {
                    "range": [
                      {
                        "fixed": "a2ab6d409d2676eb0711ecbd737192043125b437"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "stable.20210804.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48780.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:22.740492937Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48780.json",
        "https://github.com/forem/forem/security/advisories/GHSA-3g4h-9h37-mpx6",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-48780",
        "https://github.com/forem/forem/commit/a2ab6d409d2676eb0711ecbd737192043125b437"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-287"
        ],
        "cna_assigner": "GitHub_M",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "a2ab6d4"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48780.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-48780",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 489133,
  "published_at": "2026-06-16T14:10:27.047+00:00"
}