CVE-2026-55009HighCVSS 7.8
Microsoft Exchange Server Elevation of Privilege Vulnerability
🔗 CVE IDs covered (1)
📋 Description
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
🎯 Affected products4
- Microsoft Exchange Server 2016 Cumulative Update 23
- Microsoft Exchange Server 2019 Cumulative Update 14
- Microsoft Exchange Server 2019 Cumulative Update 15
- Microsoft Exchange Server Subscription Edition RTM
✅ Remediation
KB5103215 (Security Update) — fixed build 15.01.2507.071 KB5103214 (Security Update) — fixed build 15.02.1544.043 KB5103212 (Security Update) — fixed build 15.02.2562.045 KB5103213 (Security Update) — fixed build 15.02.1748.048
🔗 References (6)
- advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55009
- referencehttps://support.microsoft.com/help/5103215
- referencehttps://support.microsoft.com/help/5103214
- patchhttps://www.microsoft.com/en-us/download/details.aspx?id=108746
- referencehttps://support.microsoft.com/help/5103212
- referencehttps://support.microsoft.com/help/5103213