{"id":"CVE-2026-50659","aliases":[],"cve":{"records":[{"id":"CVE-2026-50659","source":"microsoft","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-06-05T14:33:50.831Z","published":"2026-07-14T19:40:15.949Z","modified":"2026-10-28T20:04:51.410Z"}],"publishers":[{"name":"microsoft","role":"CNA","organizationId":"f38d906d-7342-40ea-92c1-6c4a2c6478c8","modified":"2026-10-28T20:04:51.410Z"},{"name":"CISA-ADP","role":"ADP","organizationId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","modified":"2026-07-14T20:48:09.399Z"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50659","tags":["vendor-advisory","patch"],"source":"microsoft"}],"weaknesses":[{"id":"CWE-116","description":"CWE-116: Improper Encoding or Escaping of Output","source":"microsoft"}],"applicability":[{"source":"microsoft","statements":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:visual_studio_2022:*:*:*:*:*:*:*:*","versionStartIncluding":"17.12.0","versionEndExcluding":"17.12.22"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*","versionStartIncluding":"10.0.0","versionEndExcluding":"10.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*","versionStartIncluding":"8.0.0","versionEndExcluding":"8.0.29"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*","versionStartIncluding":"9.0.0","versionEndExcluding":"9.0.18"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:visual_studio_2022:*:*:*:*:*:*:*:*","versionStartIncluding":"17.14.0","versionEndExcluding":"17.14.36"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*","versionStartIncluding":"4.8.0","versionEndExcluding":"4.8.4803.0"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*","versionStartIncluding":"4.8.0","versionEndExcluding":"2.0.50727.9069 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3.0.30729.8978"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:.net_framework:*:*:*:*:*:*:*:*","versionStartIncluding":"4.8.0.0","versionEndExcluding":"4.8.9340.0"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:visual_studio_2026:*:*:*:*:*:*:*:*","versionStartIncluding":"18.0","versionEndExcluding":"18.7.4"}]}]}]}],"prioritization":[{"source":"CISA-ADP","type":"SSVC","role":"CISA Coordinator","timestamp":"2026-07-14T20:32:29.416499Z","decisions":[{"name":"Exploitation","value":"none"},{"name":"Automatable","value":"no"},{"name":"Technical Impact","value":"partial"}]}]},"title":".NET Spoofing Vulnerability","titleSource":"microsoft","descriptionSource":"microsoft","description":"Improper encoding or escaping of output in .NET allows an authorized attacker to perform spoofing over a 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3.5","platforms":["Windows 11 Version 26H1 for ARM64-based Systems","Windows 11 version 26H1 for x64-based Systems","Windows Server 2012","Windows Server 2012 (Server Core installation)","Windows Server 2012 R2","Windows Server 2012 R2 (Server Core installation)"],"versions":[{"version":"3.5.0","status":"affected","lessThan":"2.0.50727.8983 & 3.0.30729.8978","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft .NET Framework 3.5 AND 4.7.2","platforms":["Windows 10 Version 1607 for 32-bit Systems","Windows 10 Version 1607 for x64-based Systems","Windows 10 Version 1809 for 32-bit Systems","Windows 10 Version 1809 for x64-based Systems","Windows Server 2016","Windows Server 2016 (Server Core installation)","Windows Server 2019","Windows Server 2019 (Server Core installation)"],"versions":[{"version":"4.7.0","status":"affected","lessThan":"2.0.50727.9069 & 3.0.30729.9067 & 4.7.4143.0","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft .NET Framework 3.5 AND 4.8","platforms":["Windows 10 Version 1809 for 32-bit Systems","Windows 10 Version 1809 for x64-based Systems","Windows 10 Version 21H2 for 32-bit Systems","Windows 10 Version 21H2 for ARM64-based Systems","Windows 10 Version 21H2 for x64-based Systems","Windows 10 Version 22H2 for 32-bit Systems","Windows 10 Version 22H2 for ARM64-based Systems","Windows 10 Version 22H2 for x64-based Systems","Windows Server 2019","Windows Server 2019 (Server Core installation)","Windows Server 2022","Windows Server 2022 (Server Core installation)"],"versions":[{"version":"4.8.0","status":"affected","lessThan":"2.0.50727.9069 & 3.0.30729.9067 & 4.8.4803.0","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft .NET 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4.6.2/4.7/4.7.1/4.7.2","platforms":["Windows Server 2012","Windows Server 2012 (Server Core installation)","Windows Server 2012 R2","Windows Server 2012 R2 (Server Core installation)"],"versions":[{"version":"4.7.0","status":"affected","lessThan":"4.7.4143.0","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft .NET Framework 4.8","platforms":["Windows 10 Version 1607 for 32-bit Systems","Windows 10 Version 1607 for x64-based Systems","Windows Server 2012","Windows Server 2012 (Server Core installation)","Windows Server 2012 R2","Windows Server 2012 R2 (Server Core installation)","Windows Server 2016","Windows Server 2016 (Server Core installation)"],"versions":[{"version":"4.8.0","status":"affected","lessThan":"4.8.4803.0","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft .NET Framework 4.8.1","platforms":["Windows 11 Version 26H1 for ARM64-based Systems","Windows 11 version 26H1 for x64-based Systems"],"versions":[{"version":"4.8.0.0","status":"affected","lessThan":"4.8.9340.0","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft Visual Studio 2022 version 17.12","platforms":[],"versions":[{"version":"17.12.0","status":"affected","lessThan":"17.12.22","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft Visual Studio 2022 version 17.14","platforms":[],"versions":[{"version":"17.14.0","status":"affected","lessThan":"17.14.36","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"},{"vendor":"Microsoft","name":"Microsoft Visual Studio 2026 version 18.7","platforms":[],"versions":[{"version":"18.0","status":"affected","lessThan":"18.7.4","versionType":"custom"}],"cpes":[],"source":"microsoft","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"}],"remediation":[],"references":["https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50659"],"sources":[{"name":"CVE","id":"CVE-2026-50659","modified":"2026-10-28T20:04:51.410Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"}],"assessments":[{"source":"microsoft","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C","score":6.5}],"sourceAffected":[],"observedAt":"2026-10-29T14:39:26.858Z","kev":{"status":"not-listed","checkedAt":"2026-10-31T09:10:30.844Z"},"coverage":[{"source":"NVD","status":"not-checked"},{"source":"GHSA","status":"not-checked"},{"source":"EUVD","status":"not-checked"},{"source":"EPSS","status":"not-checked"}],"evidence":[],"aiSummary":{"text":"A .NET spoofing vulnerability allows an authorized attacker to perform spoofing over a network due to improper encoding or escaping of output. The vulnerability affects various .NET runtime and framework versions. An attacker with authorized access can exploit this weakness.","model":"@cf/meta/llama-3.3-70b-instruct-fp8-fast","generatedAt":"2026-10-30T09:18:38.085Z","sources":[{"name":"CVE","url":"https://www.cve.org/CVERecord?id=CVE-2026-50659"}]}}