{"id":"CVE-2026-87696","title":"Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.","summary":"Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-347"],"published":"2026-10-13","updated":"2026-10-14","sourceUpdated":"2026-10-14T04:18:52.363","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-87696","references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87696","label":"secure@microsoft.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-10-13T19:43:29.201Z","vendor":"Microsoft","product":"Microsoft Exchange Server 2016 Cumulative Update 23","affected":["exchange_server_2016_cumulative_update_23 >= 15.01.0.0 < 15.01.2507.077","exchange_server_2019_cumulative_update_14 >= 15.02.0.0 < 15.02.1544.050","exchange_server_2019_cumulative_update_15 >= 15.02.0.0 < 15.02.1748.055","exchange_server_subscription_edition_rtm >= 15.02.0.0 < 15.02.2562.056"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-09T00:00:00+00:00"},"epss":0.00429,"epssPercentile":0.36971,"slug":"CVE-2026-87696","body":"## Overview\n\nImproper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}