Cyber Resilience

CVE-2026-44820

High

Published: 09 June 2026

Published
09 June 2026
Modified
11 June 2026
KEV Added
—
Patch
—
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0029 20.6th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-44820 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Microsoft Office 2021. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 20.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Integer underflow (wrap or wraparound) in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CWE(s)
CWE-125

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

microsoft
365 apps
all versions
microsoft
excel
2016
microsoft
microsoft 365
all versions
microsoft
office 2019
all versions
microsoft
office 2021
all versions
microsoft
office 2024
all versions
microsoft
office online server
all versions

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References