CVE-2026-78525: CWE-416: Use After Free in Microsoft Microsoft 365 Apps for Enterprise
CVE-2026-78525 is a use-after-free vulnerability in Microsoft Office Outlook within Microsoft 365 Apps for Enterprise. This flaw allows an unauthorized attacker to execute code remotely over a network. The vulnerability has a high severity with a CVSS score of 8.8. An official fix is available from Microsoft, and the vendor manages remediation for this cloud-hosted service. No known exploits are reported in the wild at this time.
AI Analysis
Technical Summary
This vulnerability, identified as CVE-2026-78525 and classified under CWE-416 (Use After Free), affects Microsoft Office Outlook in Microsoft 365 Apps for Enterprise version 16.0.1. It allows an attacker to execute arbitrary code remotely by exploiting a use-after-free condition. The vulnerability has a CVSS 3.1 base score of 8.8, indicating high impact on confidentiality, integrity, and availability. Microsoft has released an official fix and manages remediation for this cloud service. The vendor advisory is available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78525.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthorized attacker to execute arbitrary code remotely, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. This could enable actions such as data theft, system manipulation, or disruption of service.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages the remediation server-side. Users and administrators should ensure that their Microsoft 365 Apps for Enterprise environment is updated according to the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78525 to protect against this vulnerability.
CVE-2026-78525: CWE-416: Use After Free in Microsoft Microsoft 365 Apps for Enterprise
Description
CVE-2026-78525 is a use-after-free vulnerability in Microsoft Office Outlook within Microsoft 365 Apps for Enterprise. This flaw allows an unauthorized attacker to execute code remotely over a network. The vulnerability has a high severity with a CVSS score of 8.8. An official fix is available from Microsoft, and the vendor manages remediation for this cloud-hosted service. No known exploits are reported in the wild at this time.
CVSS v3.1
Score 8.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CVE-2026-78525 and classified under CWE-416 (Use After Free), affects Microsoft Office Outlook in Microsoft 365 Apps for Enterprise version 16.0.1. It allows an attacker to execute arbitrary code remotely by exploiting a use-after-free condition. The vulnerability has a CVSS 3.1 base score of 8.8, indicating high impact on confidentiality, integrity, and availability. Microsoft has released an official fix and manages remediation for this cloud service. The vendor advisory is available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78525.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthorized attacker to execute arbitrary code remotely, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. This could enable actions such as data theft, system manipulation, or disruption of service.
Mitigation Recommendations
An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages the remediation server-side. Users and administrators should ensure that their Microsoft 365 Apps for Enterprise environment is updated according to the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78525 to protect against this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-24T17:28:00.623Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Is Cloud Service
- true
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78525","vendor":"Microsoft"}]
Threat ID: 6aa04564acd9273b49faa287
Added to database: 09/08/2026, 17:27:00 UTC
Last enriched: 09/08/2026, 19:22:19 UTC
Last updated: 09/08/2026, 19:22:19 UTC
Views: 2
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