{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": [
              "cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:*",
              "cpe:2.3:a:facebook:hhvm:3.30:*:*:*:*:*:*:*"
            ],
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "last_affected": "3.27.4"
              },
              {
                "introduced": "3.30"
              },
              {
                "last_affected": "3.30"
              }
            ],
            "source": [
              "CPE_RANGE",
              "CPE_STRING",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "b14f761969e2ce2b52d7e49e40fa6c58bf43e477"
            },
            {
              "introduced": "68dd840917c9051225b38206fa61791bb68767fb"
            },
            {
              "last_affected": "68dd840917c9051225b38206fa61791bb68767fb"
            },
            {
              "fixed": "4bff3bfbe90d10451e4638c2118d1ad1117bb3e3"
            }
          ],
          "repo": "https://github.com/facebook/hhvm",
          "type": "GIT"
        }
      ],
      "versions": [
        "3.30"
      ]
    }
  ],
  "database_specific": {},
  "details": "The Memcache::getextendedstats function can be used to trigger an out-of-bounds read. Exploiting this issue requires control over memcached server hostnames and/or ports. This affects all supported versions of HHVM (3.30 and 3.27.4 and below).",
  "id": "CVE-2018-6340",
  "modified": "2026-07-08T05:36:12.599516126Z",
  "published": "2018-12-31T22:29:00.327Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://hhvm.com/blog/2018/12/18/hhvm-3.30.1.html"
    },
    {
      "type": "FIX",
      "url": "https://github.com/facebook/hhvm/commit/4bff3bfbe90d10451e4638c2118d1ad1117bb3e3"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}