{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.05"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "f28768ed1d4f3b758bd43f2fd01d26f748b1c88d"
            },
            {
              "fixed": "760bb358b8f53e52cf415888a4ac858fd99bb24e"
            }
          ],
          "repo": "https://github.com/kazeburo/plack-middleware-session-simple",
          "type": "GIT"
        }
      ]
    }
  ],
  "details": "Plack::Middleware::Session::Simple versions before 0.05 for Perl generates session ids insecurely.\n\nThe default session id generator returns a SHA-1 hash seeded with the built-in rand function, the epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage.\n\nPredictable session ids could allow an attacker to gain access to systems.\n\nPlack::Middleware::Session::Simple is intended to be compatible with Plack::Middleware::Session, which had a similar security issue CVE-2025-40923.",
  "id": "CVE-2025-40926",
  "modified": "2026-03-13T21:49:34.782641387Z",
  "published": "2026-03-05T02:16:39.790Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.05/changes"
    },
    {
      "type": "ADVISORY",
      "url": "https://security.metacpan.org/docs/guides/random-data-for-security.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-40923"
    },
    {
      "type": "REPORT",
      "url": "https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.04/source/lib/Plack/Middleware/Session/Simple.pm#L43"
    },
    {
      "type": "FIX",
      "url": "https://github.com/kazeburo/Plack-Middleware-Session-Simple/commit/760bb358b8f53e52cf415888a4ac858fd99bb24e.patch"
    },
    {
      "type": "FIX",
      "url": "https://github.com/kazeburo/Plack-Middleware-Session-Simple/pull/4"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}