{"id":"CVE-2026-103577","state":"PUBLISHED","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.","publishedAt":"2026-10-13T19:01:36.543Z","updatedAt":"2026-10-30T19:14:16.970Z","severity":{"score":7.5,"label":"High","version":"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","source":"microsoft"},"assigner":"microsoft","products":["Microsoft Windows 11 version 23H2","Microsoft Windows 11 Version 23H2","Microsoft Windows 11 Version 24H2","Microsoft Windows 11 Version 25H2","Microsoft Windows 11 version 26H1","Microsoft Windows 11 Version 26H2","Microsoft Windows Server 2022","Microsoft Windows Server 2025","Microsoft Windows Server 2025 (Server Core installation)"],"affected":[{"vendor":"Microsoft","product":"Windows 11 version 23H2","versions":[{"version":"10.0.22631.0","status":"affected","lessThan":"10.0.22631.7652","versionType":"custom"}],"platforms":["ARM64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 23H2","versions":[{"version":"10.0.22631.0","status":"affected","lessThan":"10.0.22631.7652","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 24H2","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 25H2","versions":[{"version":"10.0.26200.0","status":"affected","lessThan":"10.0.26200.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 version 26H1","versions":[{"version":"10.0.28000.0","status":"affected","lessThan":"10.0.28000.3231","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 26H2","versions":[{"version":"10.0.26300.0","status":"affected","lessThan":"10.0.26300.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2022","versions":[{"version":"10.0.20348.0","status":"affected","lessThan":"10.0.20348.5761","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2025","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.33650","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2025 (Server Core installation)","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.33650","versionType":"custom"}],"platforms":["x64-based Systems"]}],"references":["https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-103577"],"weaknesses":["CWE-453"],"ingestedAt":"2026-10-30T19:40:06.317Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/103xxx/CVE-2026-103577.json","commit":"91beacf46587178cb335e3399e6db92524d41de0","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-103577","state":"PUBLISHED","datePublished":"2026-10-13T19:01:36.543Z","dateUpdated":"2026-10-30T19:14:16.970Z","assignerShortName":"microsoft","assignerOrgId":"f38d906d-7342-40ea-92c1-6c4a2c6478c8","dateReserved":"2026-09-30T20:48:29.840Z"},"containers":{"cna":{"title":"Microsoft QUIC Security Feature Bypass Vulnerability","descriptions":[{"lang":"en-US","value":"Insecure default variable initialization in Microsoft QUIC allows an unauthorized attacker to bypass a security feature over a network."}],"affected":[{"vendor":"Microsoft","product":"Windows 11 version 23H2","versions":[{"version":"10.0.22631.0","status":"affected","lessThan":"10.0.22631.7652","versionType":"custom"}],"platforms":["ARM64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 23H2","versions":[{"version":"10.0.22631.0","status":"affected","lessThan":"10.0.22631.7652","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 24H2","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 25H2","versions":[{"version":"10.0.26200.0","status":"affected","lessThan":"10.0.26200.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 version 26H1","versions":[{"version":"10.0.28000.0","status":"affected","lessThan":"10.0.28000.3231","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows 11 Version 26H2","versions":[{"version":"10.0.26300.0","status":"affected","lessThan":"10.0.26300.9711","versionType":"custom"}],"platforms":["ARM64-based Systems","x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2022","versions":[{"version":"10.0.20348.0","status":"affected","lessThan":"10.0.20348.5761","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2025","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.33650","versionType":"custom"}],"platforms":["x64-based Systems"]},{"vendor":"Microsoft","product":"Windows Server 2025 (Server Core installation)","versions":[{"version":"10.0.26100.0","status":"affected","lessThan":"10.0.26100.33650","versionType":"custom"}],"platforms":["x64-based Systems"]}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-103577","name":"Microsoft QUIC Security Feature Bypass Vulnerability","tags":["vendor-advisory","patch"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en-US","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","baseSeverity":"HIGH","baseScore":7.5,"vectorString":"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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-453","description":"CWE-453: Insecure Default Variable Initialization","lang":"en-US","type":"CWE"}]}],"providerMetadata":{"shortName":"microsoft","orgId":"f38d906d-7342-40ea-92c1-6c4a2c6478c8","dateUpdated":"2026-10-30T19:14:16.970Z"},"datePublic":"2026-10-13T14:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:windows_11_version_26h2_for_arm64-based_systems:*:*:*:*:*:*:*:*","versionStartIncluding":"10.0.26300.0","versionEndExcluding":"10.0.26300.9711"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*","versionStartIncluding":"10.0.20348.0","versionEndExcluding":"10.0.20348.5761"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_11_23H2:*:*:*:*:*:*:x64:*","versionStartIncluding":"10.0.22631.0","versionEndExcluding":"10.0.22631.7652"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_11_24H2:*:*:*:*:*:*:x64:*","versionStartIncluding":"10.0.26100.0","versionEndExcluding":"10.0.26100.9711"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_11_25H2:*:*:*:*:*:*:arm64:*","versionStartIncluding":"10.0.26200.0","versionEndExcluding":"10.0.26200.9711"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*","versionStartIncluding":"10.0.26100.0","versionEndExcluding":"10.0.26100.33650"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_11_23H2:*:*:*:*:*:*:arm64:*","versionStartIncluding":"10.0.22631.0","versionEndExcluding":"10.0.22631.7652"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*","versionStartIncluding":"10.0.26100.0","versionEndExcluding":"10.0.26100.33650"},{"vulnerable":true,"criteria":"cpe:2.3:o:microsoft:windows_11_26H1:*:*:*:*:*:*:arm64:*","versionStartIncluding":"10.0.28000.0","versionEndExcluding":"10.0.28000.3231"}]}]}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-103577","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-13T22:08:27.514406Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-13T22:16:33.980Z"}}]}}}