Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
cve-program · CVE-2026-86056
PublishedNotepad++ 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.
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cve-program · CVE-2026-86056
PublishedNotepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
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.
- Source published
- 22 Sep 2026 17:14:13 UTC
- Source modified
- 22 Sep 2026 17:40:34 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H