CVE-2026-86056

Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)

Published: Sep 22, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-476

5.5MEDIUM

Description

Notepad++ is a free and open-source source code editor. Prior to 8.9.8, the NPPM_SAVESESSION handler in PowerEditor/src/NppBigSwitch.cpp converts lParam to a sessionInfo pointer and dereferences its nbFile, files, and sessionFilePathName members without checking for null. A process running at the same or a higher Windows integrity level on the same desktop can send NPPM_SAVESESSION with a null lParam, immediately terminating Notepad++ and causing denial of service and loss of unsaved documents. This issue is fixed in version 8.9.8.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:LAttack Vector

Local

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-476

Affected Products

notepad-plus-plus

commercialaka notepad plus plus, notepad+ plus, notepad++

notepad-plus-plusOn-prem

Consumer Software / productivity

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

https://github.com/notepad-plus-plus/notepad-plus-plus/commit/8b33f52e7aa488b1222d3cfce5903a38dd63101f

github.com

https://github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8

github.com

https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-j85c-6wc9-p98p

github.com

and 1 more references View all →

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