CVE-2026-42831

HIGH
MEDIUM Priority: 0.03 BB Relevance: 41/100
Published: 2026-05-12 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Auth Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: None
UI: Required
S: Unchanged
C: High
I: High
A: High

Description

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Weakness Classification (1)

Affected Software (3)

VendorProductVersion
microsoft 365_copilot < 16.0.19822.20190
microsoft office 2024
microsoft office_long_term_servicing_channel 2021

References & Advisories (1)

Bug Bounty Relevance

41 / 100
✓ No authentication
✓ Low complexity

CVSS Score

7.8 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.44%
Raw Score 0.004370
Percentile 37.9%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00437
2026-10-28
0.00437

Intelligence Sources

nvd ref →