Description
Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Published: 2026-07-14
Score: 7.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

An untrusted pointer dere allows an unauthorized attacker to execute code locally. The flaw is limited to the Excel component and can lead to full compromise of the system on which the file is opened.

Affected Systems

Microsoft 365 Apps for Enterprise, Microsoft Excel 2016, Microsoft Office 2019, Microsoft Office 365 for Mac, Microsoft Office LTSC 2021, Microsoft Office LTSC 2024, Microsoft Office LTSC for Mac 2021, Microsoft Office LTSC for Mac 2024, and Microsoft Office Online Server.

Risk and Exploitability

The CVSS v3.1 score of 7.8 indicates medium–high risk. The EPSS score of less than 1 % points to a low probability of active exploitation in the wild. The vulnerability is not listed in CISA’s KEV catalog. The description does not explicitly state how the attacker achieves execution; based on the description, it is inferred that the vulnerability would be triggered when Excel processes an untrusted file, requiring the user to open or otherwise allow Excel to read a malicious workbook. If successful, the attacker privileges with the rights of the user opening the file.

Generated by OpenCVE AI on July 31, 2026 at 06:55 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Apply the latest Office update that addresses CVE‑2026‑55136, via Microsoft Update or Office Central Server.
  • Ensure automatic affected Office products receive future security patches without manual intervention.
  • Configure Office to accept only files from trusted locations and disable features that execute untrusted code, such as ActiveX controls, following what is appropriate for CWE‑822 (untrusted pointer dereference).
  • Limit file type and macro execution within Excel and block any workbook that fails validation checks, thereby reducing the chance that a malicious pointer dere is processed.

Generated by OpenCVE AI on July 31, 2026 at 06:55 UTC.

Tracking

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Advisories

No advisories yet.

History

Tue, 14 Jul 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

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


Tue, 14 Jul 2026 17:45:00 +0000

Type Values Removed Values Added
Description Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Title Microsoft Excel Remote Code Execution Vulnerability
First Time appeared Microsoft
Microsoft 365 Apps
Microsoft excel 2016
Microsoft office 2019
Microsoft office 2021
Microsoft office 2024
Microsoft office 365
Microsoft office Macos 2021
Microsoft office Macos 2024
Weaknesses CWE-822
CPEs cpe:2.3:a:microsoft:365_apps:*:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:excel_2016:*:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_2019:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_2021:*:*:*:*:long_term_servicing_channel:*:*:*
cpe:2.3:a:microsoft:office_2021:*:*:*:*:ltsc:*:*:*
cpe:2.3:a:microsoft:office_2024:*:*:*:*:long_term_servicing_channel:*:*:*
cpe:2.3:a:microsoft:office_365:*:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_macos_2021:*:*:*:*:*:long_term_servicing_channel:*:*
cpe:2.3:a:microsoft:office_macos_2024:*:*:*:*:*:long_term_servicing_channel:*:*
Vendors & Products Microsoft
Microsoft 365 Apps
Microsoft excel 2016
Microsoft office 2019
Microsoft office 2021
Microsoft office 2024
Microsoft office 365
Microsoft office Macos 2021
Microsoft office Macos 2024
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}


Subscriptions

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

Status: PUBLISHED

Assigner: microsoft

Published:

Updated: 2026-08-03T22:57:09.007Z

Reserved: 2026-06-16T15:03:49.681Z

Link: CVE-2026-55136

cve-icon Vulnrichment

Updated: 2026-07-14T19:03:25.631Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-31T07:00:08Z

Weaknesses
  • CWE-822

    Untrusted Pointer Dereference