Buffer overflow in Microsoft 365 Apps

CVE-2026-45466

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-45466: held from 0.004 to 0.005.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45466?
CVE-2026-45466 is a low-severity vulnerability in Microsoft 365 Apps, classified under Heap-based Buffer Overflow. CVSS score: 3.3/10. Published 2026-06-09.
How severe is CVE-2026-45466?
Low severity. CVSS v3 base score is 3.3 out of 10.