{"id":"CVE-2025-55234","aliases":["EUVD-2025-27294","GHSA-9x8h-hfmc-8j5r"],"status":"published","title":"Windows SMB Elevation of Privilege Vulnerability","description":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates.  See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.","severity":{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.20824,"percentile":0.97582,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-287"],"published":"2025-09-09T17:01:32Z","modified":"2026-06-17T09:41:30Z","exploits":[{"source":"pocgithub","id":"mrk336/CVE-2025-55234","title":"mrk336/CVE-2025-55234","date":"2025-09-13","url":"https://github.com/mrk336/CVE-2025-55234"},{"source":"pocgithub","id":"mrk336/Patch-the-Path-CVE-2025-55234-Detection-Defense","title":"mrk336/Patch-the-Path-CVE-2025-55234-Detection-Defense","date":"2025-09-15","url":"https://github.com/mrk336/Patch-the-Path-CVE-2025-55234-Detection-Defense"}],"products":[{"vendor":"microsoft","product":"windows 10 version 1507"},{"vendor":"microsoft","product":"windows 10 version 1607"},{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 21h2"},{"vendor":"microsoft","product":"windows 10 version 22h2"},{"vendor":"microsoft","product":"windows 11 version 22h2"},{"vendor":"microsoft","product":"windows 11 version 22h3"},{"vendor":"microsoft","product":"windows 11 version 23h2"},{"vendor":"microsoft","product":"windows 11 version 24h2"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1 (server core installation)"},{"vendor":"microsoft","product":"windows server 2008 service pack 2"},{"vendor":"microsoft","product":"windows server 2008 service pack 2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012"},{"vendor":"microsoft","product":"windows server 2012 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012 r2"},{"vendor":"microsoft","product":"windows server 2012 r2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2016"},{"vendor":"microsoft","product":"windows server 2016 (server core installation)"},{"vendor":"microsoft","product":"windows server 2019"},{"vendor":"microsoft","product":"windows server 2019 (server core installation)"},{"vendor":"microsoft","product":"windows server 2022"},{"vendor":"microsoft","product":"windows server 2022, 23h2 edition (server core installation)"},{"vendor":"microsoft","product":"windows server 2025"},{"vendor":"microsoft","product":"windows server 2025 (server core installation)"},{"vendor":"microsoft","product":"windows_10_1507"},{"vendor":"microsoft","product":"windows_10_1607"},{"vendor":"microsoft","product":"windows_10_1809"},{"vendor":"microsoft","product":"windows_10_21h2"},{"vendor":"microsoft","product":"windows_10_22h2"},{"vendor":"microsoft","product":"windows_11_22h2"},{"vendor":"microsoft","product":"windows_11_23h2"},{"vendor":"microsoft","product":"windows_11_24h2"},{"vendor":"microsoft","product":"windows_server_2008"},{"vendor":"microsoft","product":"windows_server_2012"},{"vendor":"microsoft","product":"windows_server_2016"},{"vendor":"microsoft","product":"windows_server_2019"},{"vendor":"microsoft","product":"windows_server_2022"},{"vendor":"microsoft","product":"windows_server_2022_23h2"},{"vendor":"microsoft","product":"windows_server_2025"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55234","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://www.vicarius.io/vsociety/posts/cve-2025-55234-detection-script-smb-server-vulnerability-affecting-microsoft-systems"},{"url":"https://www.vicarius.io/vsociety/posts/cve-2025-55234-mitigation-script-smb-server-vulnerability-affecting-microsoft-systems"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-55234"},{"url":"https://github.com/advisories/GHSA-9x8h-hfmc-8j5r"}],"sources":{"cve":[{"id":"CVE-2025-55234","title":"Windows SMB Elevation of Privilege Vulnerability","description":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates.  See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.","status":"published","published":"2025-09-09T17:01:32.635Z","modified":"2026-02-26T17:48:50.66Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:32:52.839698Z"}],"euvd":[{"id":"EUVD-2025-27294","description":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates.  See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.","status":"published","published":"2025-09-09T17:01:32Z","modified":"2026-02-26T17:48:50Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high"}],"updated_at":"2026-11-02T19:48:21.16108Z"}],"ghsa":[{"id":"GHSA-9x8h-hfmc-8j5r","title":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who...","description":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates.  See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.","status":"published","published":"2025-09-09T18:31:23Z","modified":"2025-10-17T18:32:10Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T15:04:01.2384Z"}],"nvd":[{"id":"CVE-2025-55234","description":"SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks.\nThe SMB Server already supports mechanisms for hardening against relay attacks:\n\nSMB Server signing\nSMB Server Extended Protection for Authentication (EPA)\n\nMicrosoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks.\nIf you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks:\n\nAssess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates.  See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing \u0026amp; SMB Server EPA.\nAdopt appropriate SMB Server hardening measures.","status":"published","published":"2025-09-09T17:16:06.503Z","modified":"2026-06-17T09:41:30.4Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:11:27.73916Z"}]}}