Medium severity · published Sep 22, 2026
CVE-2026-86056
Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
5.5
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
notepad-plus-plus · notepad-plus-plus
< 8.9.8 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-86056
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-86056
github.com
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
notepad-plus-plus.org
https://notepad-plus-plus.org/news/v898-released
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