{"id":"CVE-2026-55008","title":"Microsoft Exchange Server Spoofing Vulnerability","summary":"Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.","severity":"critical","cvss":9.6,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","cvssSource":"cna","cwe":["CWE-79"],"vendor":"Microsoft","product":"Microsoft Exchange Server 2016 Cumulative Update 23","affected":["exchange_server_2016_cumulative_update_23 >= 15.01.0.0 < 15.01.2507.071","exchange_server_2019_cumulative_update_14 >= 15.02.0.0 < 15.02.1544.043","exchange_server_2019_cumulative_update_15 >= 15.02.0.0 < 15.02.1748.048","exchange_server_subscription_edition_rtm >= 15.02.0.0 < 15.02.2562.045"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-07-15T03:57:27.773430Z"},"published":"2026-07-14","updated":"2026-09-17","sourceUpdated":"2026-09-17T22:29:02.641Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-55008","references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55008","label":"Microsoft Exchange Server Spoofing Vulnerability"}],"tags":["cve.org"],"epss":0.00863,"epssPercentile":0.57058,"ingestedAt":"2026-09-08T17:06:31.929Z","slug":"CVE-2026-55008","body":"## Overview\n\nImproper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.\n\n## Affected\n\n- `exchange_server_2016_cumulative_update_23 >= 15.01.0.0 < 15.01.2507.071`\n- `exchange_server_2019_cumulative_update_14 >= 15.02.0.0 < 15.02.1544.043`\n- `exchange_server_2019_cumulative_update_15 >= 15.02.0.0 < 15.02.1748.048`\n- `exchange_server_subscription_edition_rtm >= 15.02.0.0 < 15.02.2562.045`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":52.8,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}