What is CVE-2026-81385?

CVE-2026-81385 is a high-severity vulnerability in Microsoft 365 Apps, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2026-09-08.

How severe is CVE-2026-81385?

High severity. CVSS v3 base score is 8.8 out of 10.

Deserialization in Microsoft 365 Apps

CVE-2026-81385

Deserialization of untrusted data in Microsoft Office Publisher allows an unauthorized attacker to execute code over a network.

Vulnerability class: Insecure Deserialization

Published 2026-09-08 · last modified 2026-09-09.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (70.0th percentile), scored 2026-10-24.

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 70.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

Microsoft Office Publisher Remote Code Execution Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-81385?: CVE-2026-81385 is a high-severity vulnerability in Microsoft 365 Apps, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2026-09-08.
How severe is CVE-2026-81385?: High severity. CVSS v3 base score is 8.8 out of 10.