{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "3.10.22"
              },
              {
                "introduced": "3.11.0"
              },
              {
                "fixed": "3.11.17"
              },
              {
                "introduced": "3.12.0"
              },
              {
                "fixed": "3.12.15"
              },
              {
                "introduced": "3.13.0"
              },
              {
                "fixed": "3.13.16"
              },
              {
                "introduced": "3.14.0"
              },
              {
                "fixed": "3.14.8"
              },
              {
                "introduced": "3.15.0a1"
              },
              {
                "fixed": "3.15.0rc3"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "introduced": "deaf509e8fc6e0363bd6f26d52ad42f976ec42f2"
            },
            {
              "introduced": "0fb18b02c8ad56299d6a2910be0bab8ad601ef24"
            },
            {
              "introduced": "60403a5409ff2c3f3b07dd2ca91a7a3e096839c7"
            },
            {
              "introduced": "ebf955df7a89ed0c7968f79faec1de49f61ed7cb"
            },
            {
              "introduced": "f31a89bb901067dd105b00cfa90523cf7ffdbbdd"
            },
            {
              "fixed": "acb4dc12b6df8615af7b43120ef601e04072f7d2"
            },
            {
              "fixed": "e6392eb68a39cef49c9fe6431253050caa17a426"
            },
            {
              "fixed": "e848e4b09ca4bc67c0041c9ce7526dae471d4c36"
            },
            {
              "fixed": "cbc944f4bc59639a444dd971c737788ba2283a91"
            },
            {
              "fixed": "8e6e75d9102e39bed2a2b279203a396741180f12"
            },
            {
              "fixed": "8a8eb0b90d40f0e03f8252e9f73cad156e1caca8"
            },
            {
              "fixed": "34a53dce8174da2fceb12fe084a4def02a10053d"
            },
            {
              "fixed": "46133cd57d309652139ada74014aca7665ac552b"
            },
            {
              "fixed": "63fab143d94cafae71850831acfb52041ba44af7"
            },
            {
              "fixed": "b12968cefe69ca1dcb8606c832ff73ee7dbf4ba8"
            },
            {
              "fixed": "cd7e51e7d4563866fbaa1e2521ae69b45daf3698"
            },
            {
              "fixed": "d8717ed01717a9641686e6e6f83f0ab8af235e2c"
            },
            {
              "fixed": "ec44b5a3258cbda947d5e07242ee562ed05ef24b"
            }
          ],
          "repo": "https://github.com/python/cpython",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "PSF",
    "cwe_ids": [
      "CWE-416"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19445.json"
  },
  "details": "A remote, unauthenticated TLS client can make a server crash or call\nthrough a freed pointer if its sni_callback assigns a different context to\nSSLSocket.context (the documented way to select a certificate per server\nname) and nothing else keeps the original ssl.SSLContext alive. Typical\ncases are servers that create an SSLContext per connection or replace it\nwhile connections are open; servers that wrap their listening socket with\nit are not affected.\n\n\nMitigation: keep a reference to every SSLContext that sets sni_callback for\nthe lifetime of the server. TLS clients are not affected.",
  "id": "CVE-2026-19445",
  "modified": "2026-10-05T02:30:16.312041095Z",
  "published": "2026-09-30T16:16:04.923Z",
  "references": [
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/30/17"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19445.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/QMQIUQB6WGGC3MI7I3WKQXOYOBDSPPS3/"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19445"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/python/cpython/issues/156293"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/34a53dce8174da2fceb12fe084a4def02a10053d"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/46133cd57d309652139ada74014aca7665ac552b"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/63fab143d94cafae71850831acfb52041ba44af7"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/b12968cefe69ca1dcb8606c832ff73ee7dbf4ba8"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/cd7e51e7d4563866fbaa1e2521ae69b45daf3698"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/d8717ed01717a9641686e6e6f83f0ab8af235e2c"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/commit/ec44b5a3258cbda947d5e07242ee562ed05ef24b"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python/cpython/pull/158504"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/python/cpython"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Use-after-free of a server-side SSLContext when sni_callback switches contexts"
}