Vulnerability · Published Sep 8, 2026 · Assigned by microsoft
CVE-2026-69375Microsoft Exchange Server Tampering Vulnerability
Medium 6.5
In plain English
A medium-severity authorization bypass via user-controlled key in Microsoft Exchange Server 2016 Cumulative Update 23 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities).
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.6%top 48.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Authorization bypass through user-controlled key in Microsoft Exchange Server allows an authorized attacker to perform tampering over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Exchange Server 2016 Cumulative Update 23 | 15.01.0.0 – before 15.01.2507.073 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 14 | 15.02.0.0 – before 15.02.1544.046 |
| Microsoft | Microsoft Exchange Server 2019 Cumulative Update 15 | 15.02.0.0 – before 15.02.1748.051 |
| Microsoft | Microsoft Exchange Server Subscription Edition RTM | 15.02.0.0 – before 15.02.2562.049 |
Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C
References
- Microsoft Exchange Server Tampering Vulnerability vendor-advisory, patch