Is CVE-2026-26134 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-26134 being exploited in the wild.

How severe is CVE-2026-26134?

High severity, with a CVSS score of 7.8, published 10 March 2026.

Which products and versions are affected?

Microsoft 365 Copilot versions up to (excluding) 16.0.19822.20000; Microsoft Office versions up to (excluding) 16.0.19822.20000.

Is there a fix for CVE-2026-26134?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-26134 attacked?

It is attacked with local access, in a network appliance.

Am I affected by CVE-2026-26134?

Check whether you run Microsoft 365 Copilot or Microsoft Office at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-26134: Microsoft Office integer overflow in Android app

CVE-2026-26134 · Severity: high · CVSS 7.8 · Published 2026-03-10

A security vulnerability in Microsoft Office for Android could allow a user who already has basic access to a device to gain higher-level system permissions. This type of flaw is typically used by attackers to bypass security restrictions, access sensitive data, or install malicious software that would otherwise be blocked. The issue affects mobile versions of Office and Microsoft 365 Copilot.

Technologies: Microsoft 365 Copilot, Microsoft Office. Vendors: Microsoft.

Quick answers

Is CVE-2026-26134 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-26134 being exploited in the wild.
How severe is CVE-2026-26134?: High severity, with a CVSS score of 7.8, published 10 March 2026.
Which products and versions are affected?: Microsoft 365 Copilot versions up to (excluding) 16.0.19822.20000; Microsoft Office versions up to (excluding) 16.0.19822.20000.
Is there a fix for CVE-2026-26134?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-26134 attacked?: It is attacked with local access, in a network appliance.
Am I affected by CVE-2026-26134?: Check whether you run Microsoft 365 Copilot or Microsoft Office at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A vulnerability exists in Microsoft Office for Android (and Microsoft 365 Copilot) due to an integer overflow or wraparound condition, which can lead to a use-after-free scenario. An attacker with local access and low-privileged credentials can exploit this flaw to execute code with elevated privileges. The vulnerability is triggered during memory management operations where improper bounds checking allows for memory corruption. Microsoft has addressed this in version 16.0.19822.20000 and later.

Affected products

Microsoft Office versions up to (excluding) 16.0.19822.20000
Microsoft 365 Copilot versions up to (excluding) 16.0.19822.20000

Timeline

2026-03-10: disclosed
2026-03-10: advisory: Microsoft released the security update guide.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26134

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