Description
Notepad++ is a free and open-source source code editor. Prior to 8.9.8, Notepad++ contains a stack buffer overflow in NppParameters::writeSession in PowerEditor/src/Parameters.cpp because it copies a session path derived from -settingsDir= into backupPathName[MAX_PATH] with unbounded wcscpy and appends SESSION_BACKUP_EXT with unbounded wcscat. A sufficiently long settings directory causes the backup suffix to exceed the fixed stack buffer when Notepad++ saves the session, and the protected release build terminates through its stack canary, causing denial of service. This issue is fixed in version 8.9.8.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| notepad-plus-plus | notepad-plus-plus | < 8.9.8 | — |
Advisories 1
- WID-SEC-2026-2968 Notepad++: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 22, 2026
References
- https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-pxgg-96p2-c3hx
- https://github.com/notepad-plus-plus/notepad-plus-plus/commit/046af3f626be7715886412313fc18f58b30dfcaf
- https://github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8
- https://notepad-plus-plus.org/news/v898-released