CVE-2026-54758CWE-121CWE-787

CVE-2026-54758

High · published August 18, 2026

CVSS v3.1
7.8
EPSS
0%
Percentile
8.6
In the wild
Unconfirmed
What it is

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the expandNppEnvironmentStrs function in PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp copies a Notepad++ variable name between $( and ) into the fixed-size wchar_t str[MAX_PATH] stack buffer without bounding the m loop index, allowing a name of 260 or more characters to corrupt adjacent stack data, terminate the process through __report_gsfailure, and potentially execute code. This issue is fixed in version 8.9.7.

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00194 · 8.6th percentile
Weaknesses
CWE-121 · Stack-based Buffer Overflow; CWE-787 · Out-of-bounds Write
Published
2026-08-18T00:16Z
References (3)
EPSS history
Timeline
  • 17 AUG 20:05Z
    Notepad++: Stack Buffer Overflow in expandNppEnvironmentStrs
    cvelistv5