{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-27448",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-02-19T17:25:31.100Z",
        "datePublished": "2026-03-17T23:24:30.661Z",
        "dateUpdated": "2026-03-18T20:18:08.768Z"
    },
    "containers": {
        "cna": {
            "title": "pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-636",
                            "lang": "en",
                            "description": "CWE-636: Not Failing Securely ('Failing Open')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "HIGH",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "LOW",
                        "vulnAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 1.7,
                        "baseSeverity": "LOW",
                        "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424"
                },
                {
                    "name": "https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa0"
                },
                {
                    "name": "https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst#L27",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst#L27"
                }
            ],
            "affected": [
                {
                    "vendor": "pyca",
                    "product": "pyopenssl",
                    "versions": [
                        {
                            "version": ">= 0.14.0, < 26.0.0",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-03-17T23:24:30.661Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version 26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception, this would result in a connection being accepted. If a user was relying on this callback for any security-sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now result in rejecting the connection."
                }
            ],
            "source": {
                "advisory": "GHSA-vp96-hxj8-p424",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-03-18T20:17:52.492201Z",
                                "id": "CVE-2026-27448",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-03-18T20:18:08.768Z"
                }
            }
        ]
    }
}