CVE-2026-68553

{
  "id": "CVE-2026-68553",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-19T21:17:28.163",
  "lastModified": "2026-10-26T10:10:00.140",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "Coturn es una implementación gratuita de código abierto de servidor TURN y STUN. Antes de 4.13.0, un usuario TURN autenticado puede colocar especificadores de formato estilo printf en el atributo STUN USERNAME o REALM, lo que pasa la validación de is_secure_string() y se incrusta en las claves de Redis en nueve sitios de llamada en src/apps/relay/ns_ioalib_engine_impl.c. send_message_to_redis() en src/apps/relay/hiredis_libevent2.c luego pasa la clave controlada por el atacante como argumento de formato a redisAsyncCommand() mientras suministra solo un valor variádico, lo que hace que hiredis redisvFormatCommand() lea más allá de la va_list. La explotación puede bloquear el proceso de coturn y terminar las sesiones TURN activas o divulgar la memoria de la pila en Redis. Este problema se corrige en la versión 4.13.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "coturn",
          "product": "coturn",
          "versions": [
            {
              "version": "< 4.13.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-20T19:48:40.817549Z",
          "id": "CVE-2026-68553",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-134"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/coturn/coturn/commit/8fa38032bb4751e11e072d65a8eca3c06c950979",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/coturn/coturn/releases/tag/4.13.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/coturn/coturn/security/advisories/GHSA-4g7c-p5wg-j4hp",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/coturn/coturn/security/advisories/GHSA-4g7c-p5wg-j4hp",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}