Recorded 15 Oct 2026 at 21:30 UTC. This is what ChangeIntel recorded, including the title, summary, facts and links. It is not a statement of the source's current position.
See the latest record.
The historical field “Public exploit code” recorded Nuclei detection-template membership. It did not establish exploit availability. The original recorded fields remain below.
The historical “Publicly disclosed: No” field could represent a missing MSRC assessment. It does not establish that the vulnerability was undisclosed. The original recorded fields remain below.
CVEMicrosoft Security Response Center
Microsoft Exchange Server Tampering Vulnerability
Authorization bypass through user-controlled key in Microsoft Exchange Server allows an authorized attacker to perform tampering over a network.
CWE-639: Authorization Bypass Through User-Controlled Key
Issued by
Microsoft
Customer action
Required: apply the update
Affected products
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
Updates that fix it
KB5121608: Microsoft Exchange Server Subscription Edition RTM (restart required); KB5121609: Microsoft Exchange Server 2019 Cumulative Update 15 (restart required); KB5121610: Microsoft Exchange Server 2019 Cumulative Update 14 (restart required); KB5121611: Microsoft Exchange Server 2016 Cumulative Update 23 (restart required)