CVE-2026-69355: CWE-73: External Control of File Name or Path in Microsoft Microsoft Exchange Server 2016 Cumulative Update 23
Description
CVE-2026-69355 is a high-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23 that allows an authorized attacker to execute code remotely by externally controlling file names or paths. The vulnerability affects specific versions prior to certain build numbers and has an official fix available from Microsoft.
CVSS v3.1
Score 8.8high
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 (CVE-2026-69355) involves external control of file name or path in Microsoft Exchange Server 2016 Cumulative Update 23. An authorized attacker can exploit this flaw to execute arbitrary code over a network. The CVSS 3.1 base score is 8.8, indicating high severity, with network attack vector, low attack complexity, and no user interaction required. The vulnerability impacts confidentiality, integrity, and availability. Microsoft has published an official fix for affected versions.
Potential Impact
Successful exploitation allows an authorized attacker to execute arbitrary code remotely on the affected Microsoft Exchange Server, potentially leading to full compromise of the system. The vulnerability impacts confidentiality, integrity, and availability of the server.
Mitigation Recommendations
An official fix is available from Microsoft. Users should apply the security updates provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69355 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-03T20:52:08.512Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69355","vendor":"Microsoft"}]
Threat ID: 6aa044e9acd9273b49fa7ea7
Added to database: 09/08/2026, 17:24:57 UTC
Last enriched: 10/16/2026, 21:06:00 UTC
Last updated: 10/23/2026, 15:10:14 UTC
Views: 54
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