{"basis":"claimed","id":"CVE-2026-62911","name":"Microsoft Exchange Server Elevation of Privilege Vulnerability","vendorProject":"Microsoft","product":"Microsoft Exchange Server 2016 Cumulative Update 23","publishedAt":"2026-08-11","cvss":{"score":8,"severity":"HIGH","version":"3.1"},"exploited":null,"epss":{"score":0.00694,"percentile":0.52941,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"none","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-10-21","daysToRule":71},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"title":"Microsoft Exchange Server Elevation of Privilege Vulnerability","description":"Authentication bypass by capture-replay in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.","cwes":["CWE-294"],"vendors":[{"vendor":"cloudflare","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-10-21","firstIsNew":true,"daysToRule":71,"daysAtMost":null,"freePlan":false,"claims":[{"id":"d14729f308bd664dd3b109e6768875343cb4b4ae99ab5c4ccee1dfd46520ee83","cve_id":"CVE-2026-62911","vendor":"f5","product":"Attack signatures","rule_id":"200013238","rule_name":"Microsoft Exchange MRSProxy Authentication Bypass","change":"new","default_action":null,"published_on":"2026-10-21","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200013238 \"Microsoft Exchange MRSProxy Authentication Bypass\" (Authentication/Authorization Attacks, risk High), systems: Outlook Web Access. References: CVE-2026-62911.","first_seen_at":"2026-11-02T21:00:23.824Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-02T21:17:16.628Z","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"total"},"measured":[],"social":{"total":1,"first_seen":"2026-11-02T21:32:18.000Z","daily":[{"day":"2026-10-20","posts":0},{"day":"2026-10-21","posts":0},{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":1}],"top_posts":[],"exploit_repositories":[{"source":"github","kind":"poc","url":"https://github.com/c5z54/cve-2026-62911-poc","author":"c5z54","author_name":null,"avatar_url":"https://avatars.githubusercontent.com/u/348516981?v=4","text":"c5z54/cve-2026-62911-poc: CVE-2026-62911 — Exchange MRSProxy Pre-Auth RCE PoC | Scanner + Exploit | NTLM Relay → Webshell → SYSTEM","engagement":1,"posted_at":"2026-11-02T21:32:18.000Z"}]}}