{"id":"CVE-2026-40400","title":"Relative path traversal in Windows PowerShell allows an authorized attacker to execute code over a network.","summary":"Relative path traversal in Windows PowerShell allows an authorized attacker to execute code over a network.","severity":"high","cvss":8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","cwe":["CWE-23"],"vendor":"microsoft","product":"windows_10_1607","affected":["windows_10_1607 < 10.0.14393.9339","windows_10_1809 < 10.0.17763.9020","windows_10_21h2 < 10.0.19044.7548","windows_10_22h2 < 10.0.19045.7548","windows_11_24h2 < 10.0.26100.8875","windows_11_25h2 < 10.0.26200.8875","windows_11_26h1 < 10.0.28000.2269","windows_server_2012","windows_server_2012 = r2","windows_server_2016 < 10.0.14393.9339","windows_server_2019 < 10.0.17763.9020","windows_server_2022 < 10.0.20348.5386","windows_server_2025 < 10.0.26100.33158"],"patched":["windows_10_1607 10.0.14393.9339","windows_10_1809 10.0.17763.9020","windows_10_21h2 10.0.19044.7548","windows_10_22h2 10.0.19045.7548","windows_11_24h2 10.0.26100.8875","windows_11_25h2 10.0.26200.8875","windows_11_26h1 10.0.28000.2269","windows_server_2016 10.0.14393.9339","windows_server_2019 10.0.17763.9020","windows_server_2022 10.0.20348.5386","windows_server_2025 10.0.26100.33158"],"published":"2026-07-14","updated":"2026-09-17","sourceUpdated":"2026-09-17T23:17:03.933","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-40400","references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40400","label":"secure@microsoft.com"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-07-14T00:00:00+00:00"},"epss":0.00868,"epssPercentile":0.5672,"ingestedAt":"2026-07-17T13:12:08.623Z","slug":"CVE-2026-40400","body":"## Overview\n\nRelative path traversal in Windows PowerShell allows an authorized attacker to execute code over a network.\n\n## Affected\n\n- `windows_10_1607 < 10.0.14393.9339`\n- `windows_10_1809 < 10.0.17763.9020`\n- `windows_10_21h2 < 10.0.19044.7548`\n- `windows_10_22h2 < 10.0.19045.7548`\n- `windows_11_24h2 < 10.0.26100.8875`\n- `windows_11_25h2 < 10.0.26200.8875`\n- `windows_11_26h1 < 10.0.28000.2269`\n- `windows_server_2012`\n- `windows_server_2012 = r2`\n- `windows_server_2016 < 10.0.14393.9339`\n- `windows_server_2019 < 10.0.17763.9020`\n- `windows_server_2022 < 10.0.20348.5386`\n- `windows_server_2025 < 10.0.26100.33158`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `windows_10_1607 10.0.14393.9339`\n- `windows_10_1809 10.0.17763.9020`\n- `windows_10_21h2 10.0.19044.7548`\n- `windows_10_22h2 10.0.19045.7548`\n- `windows_11_24h2 10.0.26100.8875`\n- `windows_11_25h2 10.0.26200.8875`\n- `windows_11_26h1 10.0.28000.2269`\n- `windows_server_2016 10.0.14393.9339`\n- `windows_server_2019 10.0.17763.9020`\n- `windows_server_2022 10.0.20348.5386`\n- `windows_server_2025 10.0.26100.33158`","depth":"twilight","depthScore":44,"depthScoreParts":{"impact":44,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}