Vulnerability 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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/notepad-plus-plus/notepad-plus-plus/commit/046af3f626be771588
- https://github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8
- https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-
- https://notepad-plus-plus.org/news/v898-released
- https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-
FAQ
What is CVE-2026-86054?
CVE-2026-86054 is a vulnerability with a CVSS score of 7.8 (HIGH). 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 ...
How severe is CVE-2026-86054?
CVE-2026-86054 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-86054?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.