Description
Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
Published: 2026-09-08
Score: 6.5 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Information Disclosure
Action: Apply Patch
AI Analysis

Impact

Out-of-bounds read in Microsoft Office Word allows an attacker to read data beyond the intended buffer, potentially exposing sensitive information. The flaw enables an unauthorized attacker to extract data over the network, compromising confidentiality of disclosed content. This vulnerability is a classic breach of data protection, affecting systems that rely on Office for file management and data handling.

Affected Systems

The vulnerability impacts Microsoft 365 Apps for Enterprise, Microsoft Office 2019, Microsoft Office LTSC 2021, Microsoft Office LTSC 2024, and Microsoft Word 2016. All current versions of these products are affected as indicated by the CNA. Administrators should verify that any installations of these Office suites are within the affected release set.

Risk and Exploitability

The CVSS score of 6.5 indicates a moderate severity, and the EPSS score is not available, suggesting limited information about exploitation frequency. The vulnerability is not listed in the CISA KEV catalog, but it can be abused by a remote attacker by sending specially crafted documents or macros over the network, triggering the out-of-bounds read. Attackers would need network access to the vulnerable system and the ability to deliver the exploit payload, but no privilege escalation is required.

Generated by OpenCVE AI on September 9, 2026 at 02:08 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Install the security update provided by Microsoft for all affected Office products (see the MSRC advisory link).
  • If possible, disable the Office feature or file type that triggers the out-of-bounds read to reduce the attack surface until the patch is applied.
  • Monitor network traffic and system logs for anomalous Word activity that may indicate exploitation attempts.

Generated by OpenCVE AI on September 9, 2026 at 02:08 UTC.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Tue, 08 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 08 Sep 2026 21:00:00 +0000

Type Values Removed Values Added
First Time appeared Microsoft word
CPEs cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x86:*
Vendors & Products Microsoft word

Tue, 08 Sep 2026 17:30:00 +0000

Type Values Removed Values Added
Description Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
Title Microsoft Office Word Information Disclosure Vulnerability
First Time appeared Microsoft
Microsoft 365 Apps
Microsoft office 2019
Microsoft office 2021
Microsoft office 2024
Microsoft word 2016
Weaknesses CWE-125
CPEs cpe:2.3:a:microsoft:365_apps:*:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:office_2019:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_2021:*:*:*:*:long_term_servicing_channel:*:*:*
cpe:2.3:a:microsoft:office_2024:*:*:*:*:long_term_servicing_channel:*:*:*
cpe:2.3:a:microsoft:word_2016:*:*:*:*:*:*:*:*
Vendors & Products Microsoft
Microsoft 365 Apps
Microsoft office 2019
Microsoft office 2021
Microsoft office 2024
Microsoft word 2016
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C'}


Subscriptions

Microsoft 365 Apps Office 2019 Office 2021 Office 2024 Word Word 2016
cve-icon MITRE

Status: PUBLISHED

Assigner: microsoft

Published:

Updated: 2026-09-25T21:38:25.309Z

Reserved: 2026-08-24T17:28:00.623Z

Link: CVE-2026-78522

cve-icon Vulnrichment

Updated: 2026-09-08T20:01:33.166Z

cve-icon NVD

Status : Analyzed

Published: 2026-09-08T18:20:47.813

Modified: 2026-09-08T20:49:52.020

Link: CVE-2026-78522

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-10T02:00:18Z

Weaknesses