NULL pointer dereference in Notepad++ - CVE-2026-86056
Published: August 24, 2026 / Updated: September 23, 2026
Vulnerability identifier: #VU144996
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-86056
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to null pointer dereference in the NPPM_SAVESESSION message handler in PowerEditor/src/NppBigSwitch.cpp when handling a crafted NPPM_SAVESESSION message with a null lParam pointer. A local user can send a specially crafted message to cause a denial of service.
The issue can result in loss of unsaved document data.
Affected software
Notepad++
How to mitigate CVE-2026-86056
Install security update from vendor's website.
Notepad++ - update to 8.9.8