Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
Summary
| CVE | CVE-2026-86056 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-22 18:17:24 UTC |
| Updated | 2026-09-23 18:28:25 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.001620000 probability, percentile 0.057960000 (date 2026-09-23)
Problem Types: CWE-476 | CWE-476 CWE-476: NULL Pointer Dereference
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Notepad-plus-plus | Notepad-plus-plus | affected < 8.9.8 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| notepad-plus-plus.org/news/v898-released | [email protected] | notepad-plus-plus.org | |
| github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-... | [email protected] | github.com | |
| github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8 | [email protected] | github.com | |
| github.com/notepad-plus-plus/notepad-plus-plus/commit/8b33f52e7aa488b122... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.