{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "4.13.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8fa38032bb4751e11e072d65a8eca3c06c950979"
            },
            {
              "fixed": "bd02141ad865830fdea420ca0c803edf5ba8240c"
            }
          ],
          "repo": "https://github.com/coturn/coturn",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-4g7c-p5wg-j4hp"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-134"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68553.json"
  },
  "details": "Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, an authenticated TURN user can place printf-style format specifiers in the STUN USERNAME or REALM attribute, which passes is_secure_string() validation and is embedded into Redis keys at nine call sites in src/apps/relay/ns_ioalib_engine_impl.c. send_message_to_redis() in src/apps/relay/hiredis_libevent2.c then passes the attacker-controlled key as the format argument to redisAsyncCommand() while supplying only one variadic value, causing hiredis redisvFormatCommand() to read past the va_list. Exploitation can crash the coturn process and terminate active TURN sessions or disclose stack memory into Redis. This issue is fixed in version 4.13.0.",
  "id": "CVE-2026-68553",
  "modified": "2026-08-21T11:30:10.903848124Z",
  "published": "2026-08-19T20:37:42.319Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/coturn/coturn/releases/tag/4.13.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68553.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/coturn/coturn/security/advisories/GHSA-4g7c-p5wg-j4hp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68553"
    },
    {
      "type": "FIX",
      "url": "https://github.com/coturn/coturn/commit/8fa38032bb4751e11e072d65a8eca3c06c950979"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Coturn: Format String Injection via TURN USERNAME/REALM into hiredis Redis Command"
}