CVE-2026-83891CWE-121CWE-20

CVE-2026-83891

High · published October 13, 2026

CVSS v3.1
8.8
EPSS
1%
Percentile
54.7
In the wild
Unconfirmed
What it is

Stack-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00757 · 54.7th percentile
Weaknesses
CWE-121 · Stack-based Buffer Overflow; CWE-20 · Improper Input Validation
Published
2026-10-13T23:20Z
Affected products (9)
ProductVersionsFixed in
microsoft/365_appsall versions—
microsoft/365_appsall versions—
microsoft/microsoft_365all versions—
microsoft/office_2021all versions—
microsoft/office_2021all versions—
microsoft/office_2021all versions—
microsoft/office_2024all versions—
microsoft/office_2024all versions—
microsoft/office_2024all versions—
References (1)
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83891 · [email protected]
EPSS history
Timeline
  • 15 OCT 03:34Z
    EPSS moved — → 1%
    epss
  • 13 OCT 19:00Z
    Microsoft Office Word Remote Code Execution Vulnerability
    cvelistv5
  • 13 OCT 19:00Z
    Microsoft Office Word Remote Code Execution Vulnerability
    cvelistv5