{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "last_affected": "26.26.0"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "7e46e09a9a8446ea4fa604b42eabc73441c964c7"
            }
          ],
          "repo": "https://github.com/monkeytypegame/monkeytype",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-c878-p3jh-mmjf"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-290",
      "CWE-307",
      "CWE-644"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69183.json"
  },
  "details": "Monkeytype is a minimalistic and customizable typing test. In 26.26.0 and earlier, the backend rate-limit key generator in backend/src/middlewares/rate-limit.ts uses client-controlled cf-connecting-ip and x-forwarded-for headers before the trust-proxy-derived req.ip value. An unauthenticated attacker can rotate either header to create a new bucket for each request, bypassing rootRateLimiter, badAuthRateLimiter, getKey(), and the getKeyWithUid() fallback used by public endpoints. This permits repeated POST /users/forgotPasswordEmail and verificationEmail requests, mail bombing registered users, consuming Firebase or SMTP quota, evading brute-force protection, and enabling resource exhaustion. Exploitability of cf-connecting-ip depends on deployment topology, but x-forwarded-for and direct-to-origin paths remain affected when those values are not overwritten by a trusted proxy. No fixed version is available as of this review.",
  "id": "CVE-2026-69183",
  "modified": "2026-09-20T11:31:04.346199458Z",
  "published": "2026-08-20T16:16:43.289Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69183.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/monkeytypegame/monkeytype/security/advisories/GHSA-c878-p3jh-mmjf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-69183"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Monkeytype: Rate-limit and anti-brute-force controls bypassable via spoofed HTTP headers (forgotPasswordEmail/verificationEmail mail bombing and badAuth bypass)"
}