CVE-2026-69380: CWE-862: Missing Authorization in Microsoft Microsoft Exchange Server 2016 Cumulative Update 23
Description
CVE-2026-69380 is a high-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23 involving missing authorization. It allows an authorized attacker to elevate privileges over a network without user interaction. The vulnerability affects multiple specific version ranges of Exchange Server 2016. An official fix is available from Microsoft.
CVSS v3.1
Score 8.1high
Affected software
Microsoft
Microsoft Exchange Server 2016 Cumulative Update 23
Microsoft
Microsoft Exchange Server 2019 Cumulative Update 14
Microsoft
Microsoft Exchange Server 2019 Cumulative Update 15
Microsoft
Microsoft Exchange Server Subscription Edition RTM
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-862) in Microsoft Exchange Server 2016 Cumulative Update 23 is due to missing authorization checks, enabling an attacker with some level of authorization to escalate privileges remotely. The CVSS 3.1 base score is 8.1, indicating high severity with network attack vector, low attack complexity, and no user interaction required. The vulnerability impacts confidentiality and integrity but not availability. Microsoft has published an official fix for affected versions.
Potential Impact
An attacker who is already authorized on the network can exploit this vulnerability to elevate their privileges, potentially gaining higher-level access than intended. This can lead to significant confidentiality and integrity breaches within the affected Exchange Server environment. There is no indication of availability impact or known exploits in the wild at this time.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. Administrators should apply the provided security updates for Microsoft Exchange Server 2016 Cumulative Update 23 to remediate this issue. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69380 for detailed patching instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-03T20:54:04.487Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69380","vendor":"Microsoft"}]
Threat ID: 6aa044edacd9273b49fa7f06
Added to database: 09/08/2026, 17:25:01 UTC
Last enriched: 10/16/2026, 21:08:02 UTC
Last updated: 10/23/2026, 15:10:14 UTC
Views: 42
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