What is the CVSS score of CVE-2026-68795?

CVE-2026-68795 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.3%.

Which versions of Microsoft Excel are affected by CVE-2026-68795?

Microsoft Office Excel contains a buffer overflow vulnerability enabling arbitrary code execution when users open malicious spreadsheets, placing employee workstations and organizational data at…. A patch is available.

How to fix or mitigate CVE-2026-68795?

Within 24 hours, implement user awareness messaging to avoid opening Excel files from untrusted external sources and establish a process for validating file origin before opening. Within 7 days, inventory Excel usage across the organization, prioritize workstations handling financial data or sensitive information, enable Office Protected View settings to restrict macro and external content execution, and deploy email gateway rules to inspect or quarantine Excel attachments from external senders. Within 30 days, establish a rapid patch deployment process and maintain continuous monitoring of Microsoft security advisories to deploy fixes immediately upon availability, with priority given to systems handling critical business functions.

Microsoft Excel CVE-2026-68795

EUVD-2026-56454 HIGH

Stack-based Buffer Overflow (CWE-121)

2026-08-11 secure@microsoft.com

GHSA-w2v7-4mj3-h376

Buffer Overflow Microsoft Stack Overflow 365 Apps Excel Microsoft 365 Office 2021 Office 2024 Office 2019

7.8

CVSS 3.1 · Vendor: microsoft

Severity by source

Vendor (microsoft) PRIMARY

7.8 HIGH

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

vuln.today AI

7.8 HIGH

AV:L and UI:R reflect file-based delivery requiring victim to open locally; PR:N because attacker needs no system account; full C/I/A from arbitrary code execution in user context.

3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

4.0 AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (microsoft).

CVSS VectorVendor: microsoft

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Patch available

Aug 11, 2026 - 18:19 EUVD

Analysis Generated

Aug 11, 2026 - 18:10 vuln.today

CVE Published

Aug 11, 2026 - 17:19 nvd

HIGH 7.8

DescriptionCVE.org

Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

AnalysisAI

Stack-based buffer overflow in Microsoft Office Excel enables arbitrary code execution on the victim's local machine when a specially crafted Excel file is opened. The vulnerability carries a CVSS base score of 7.8 with high confidentiality, integrity, and availability impact, affecting the victim's user-level security context. No public exploit has been identified at time of analysis, and the vulnerability is not listed in the CISA KEV catalog, reducing immediacy compared to actively exploited file-format parsing flaws.

Technical ContextAI

CWE-121 (Stack-based Buffer Overflow) identifies the root cause as Excel failing to validate or bound-check data written into a stack-allocated buffer during document parsing. Overflowing the stack buffer allows an attacker to overwrite the return address or adjacent function pointers, redirecting execution flow to attacker-controlled code. The CVSS vector AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H is characteristic of Office file-format parsing vulnerabilities: the attack surface is local (triggered when the file is opened), requires no attacker privileges, but requires the victim to actively open the file. Exact affected CPE strings, Office version ranges, and build numbers are not included in the available intelligence; the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68795 should be consulted for authoritative product scope.

RemediationAI

Apply the patch issued by Microsoft via the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68795. The exact patched version number is not confirmed in the available intelligence - consult the MSRC page directly for fix versions and associated KB articles. As a compensating control prior to patching, ensure Excel's Protected View is enabled for files received from the internet and email attachments, which opens untrusted documents in a read-only sandbox and blocks the parsing path that triggers this overflow. Additionally, consider enabling Microsoft Defender Application Guard for Office, which fully isolates document-opening sessions from the host OS - note that Application Guard requires Windows 10/11 Enterprise or Pro and specific hardware virtualization support. Restricting users from opening Excel attachments directly in email clients (forcing download to disk for inspection first) can reduce the social-engineering attack surface. These controls reduce exposure but do not remediate the underlying vulnerability.