{"id":"CVE-2026-103577","revision":"fdc6931b3a574de9bd7280795741164e","records":[{"revision":"fdc6931b3a574de9bd7280795741164e","observedAt":"2026-10-23T18:48:20.63+00:00","statement":{"source":"cve-program","id":"CVE-2026-103577","aliases":[],"title":"Microsoft QUIC Security Feature Bypass Vulnerability","description":"Insecure default variable initialization in Microsoft QUIC allows an unauthorized attacker to bypass a security feature over a network.","state":0,"publishedAt":"2026-10-13T19:01:36.543+00:00","modifiedAt":"2026-10-23T17:55:22.384+00:00","affected":[{"ecosystem":"Vendor product","name":"Windows 11 version 23H2","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 version 23H2\",\n                    \"platforms\": [\n                        \"ARM64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.22631.0\",\n                            \"lessThan\": \"10.0.22631.7652\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows 11 Version 23H2","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 Version 23H2\",\n                    \"platforms\": [\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.22631.0\",\n                            \"lessThan\": \"10.0.22631.7652\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows 11 Version 24H2","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 Version 24H2\",\n                    \"platforms\": [\n                        \"ARM64-based Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.26100.0\",\n                            \"lessThan\": \"10.0.26100.9711\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows 11 Version 25H2","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 Version 25H2\",\n                    \"platforms\": [\n                        \"ARM64-based Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.26200.0\",\n                            \"lessThan\": \"10.0.26200.9711\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows 11 version 26H1","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 version 26H1\",\n                    \"platforms\": [\n                        \"ARM64-based Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.28000.0\",\n                            \"lessThan\": \"10.0.28000.3231\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows 11 Version 26H2","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows 11 Version 26H2\",\n                    \"platforms\": [\n                        \"ARM64-based Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.26300.0\",\n                            \"lessThan\": \"10.0.26300.9711\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows Server 2022","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows Server 2022\",\n                    \"platforms\": [\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.20348.0\",\n                            \"lessThan\": \"10.0.20348.5761\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows Server 2025","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows Server 2025\",\n                    \"platforms\": [\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.26100.0\",\n                            \"lessThan\": \"10.0.26100.33650\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Windows Server 2025 (Server Core installation)","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Windows Server 2025 (Server Core installation)\",\n                    \"platforms\": [\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10.0.26100.0\",\n                            \"lessThan\": \"10.0.26100.33650\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H/E:U/RL:O/RC:C","score":7.5,"severity":"HIGH"}],"references":["https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-103577"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-103577","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-103577","identifiers":["CVE-2026-103577"]},"retained":false,"historicalAffected":[]}],"coverage":[]}