CVE-2025-15556

Notepad++ versions prior to 8.8.9, when using the WinGUp updater, contain an update integrity verification vulnerability where downloaded update metadata and installers are not cryptographically verified. An attacker able to intercept or redirect update traffic can cause the updater to download and execute an attacker-controlled installer, resulting in arbitrary code execution with the privileges of the user.

Affected products

Notepad++

Notepad-plus-plus Notepad\+\+

< 8.8.9

Fix

Available

CVSS 4.0

7.7 HIGH

CVSS 3.1

7.5 HIGH

EPSS

1.7% (76th percentile)

Weakness

CWE-494

NVD status

Analyzed

Published

2026-02-03