{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "zendframework/zend-captcha"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "2.4.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "zendframework/zend-captcha"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.5.0"
            },
            {
              "fixed": "2.5.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-331"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-06-07T22:25:12Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "In Zend Framework, `Zend_Captcha_Word` (v1) and `Zend\\Captcha\\Word` (v2) generate a \"word\" for a CAPTCHA challenge by selecting a sequence of random letters from a character set. Prior to this advisory, the selection was performed using PHP\u0027s internal `array_rand()` function. This function does not generate sufficient entropy due to its usage of rand() instead of more cryptographically secure methods such as `openssl_pseudo_random_bytes()`. This could potentially lead to information disclosure should an attacker be able to brute force the random number generation.",
  "id": "GHSA-mg4x-prh7-g4mx",
  "modified": "2024-06-07T22:25:12Z",
  "published": "2024-06-07T22:25:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/zendframework/zend-captcha/commit/43c276df6e94e498bf530538aea53876a24fc47c"
    },
    {
      "type": "WEB",
      "url": "https://github.com/zendframework/zend-captcha/commit/5561ef813bb4ad814e835343289dc5077d2eb262"
    },
    {
      "type": "WEB",
      "url": "https://framework.zend.com/security/advisory/ZF2015-09"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/zendframework/zend-captcha/ZF2015-09.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/zendframework/zend-captcha"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Zend-Captcha Information Disclosure and Insufficient Entropy vulnerability"
}