CVE-2026-55124: CWE-1287: Improper Validation of Specified Type of Input in Microsoft Microsoft 365 Apps for Enterprise
Improper validation of specified type of input in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-55124) is due to improper validation of the specified type of input in Microsoft Office Word within Microsoft 365 Apps for Enterprise. An unauthorized attacker with local access could exploit this flaw to disclose information. The CVSS v3.1 base score is 5.5, reflecting a medium severity with high confidentiality impact but no integrity or availability impact. The vulnerability has an official fix available, and Microsoft manages remediation for this cloud service. No known exploits are reported in the wild.
Potential Impact
An unauthorized attacker with local access to a system running the affected Microsoft 365 Apps for Enterprise version could disclose sensitive information due to improper input validation. The confidentiality impact is high, but integrity and availability are not affected. There are no reports of active exploitation in the wild.
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 their Microsoft 365 Apps for Enterprise installations are updated to the fixed version as per Microsoft's advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55124.
CVE-2026-55124: CWE-1287: Improper Validation of Specified Type of Input in Microsoft Microsoft 365 Apps for Enterprise
Description
Improper validation of specified type of input in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
CVSS v3.1
Score 5.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-55124) is due to improper validation of the specified type of input in Microsoft Office Word within Microsoft 365 Apps for Enterprise. An unauthorized attacker with local access could exploit this flaw to disclose information. The CVSS v3.1 base score is 5.5, reflecting a medium severity with high confidentiality impact but no integrity or availability impact. The vulnerability has an official fix available, and Microsoft manages remediation for this cloud service. No known exploits are reported in the wild.
Potential Impact
An unauthorized attacker with local access to a system running the affected Microsoft 365 Apps for Enterprise version could disclose sensitive information due to improper input validation. The confidentiality impact is high, but integrity and availability are not affected. There are no reports of active exploitation in the wild.
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 their Microsoft 365 Apps for Enterprise installations are updated to the fixed version as per Microsoft's advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55124.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-06-16T15:03:49.680Z
- 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-2026-55124","vendor":"Microsoft"}]
Threat ID: 6a5676b568715ace43f0ab0a
Added to database: 07/14/2026, 17:49:41 UTC
Last enriched: 08/13/2026, 15:38:34 UTC
Last updated: 08/27/2026, 11:04:02 UTC
Views: 71
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