Vulnerability Description
Notepad++ is a free and open-source source code editor. Prior to 8.9.6.4, NppCommands.cpp checks the HMAC of the on-disk shortcuts.xml at the moment a user command fires (Time-of-Check). However, the command payload is taken from the in-memory _userCommands vector, which is populated at application startup and never re-synchronized with the on-disk file (Time-of-Use). Swapping shortcuts.xml between startup and command execution causes the HMAC check to validate a clean file while a malicious command runs. An attacker with write access to shortcuts.xml places a malicious version on disk before launch, then immediately restores the legitimate file. The HMAC check at execution time validates the restored legitimate file (check passes), while the malicious payload executes from memory. This vulnerability is fixed in 8.9.6.4.
Related Weaknesses (CWE)
References
- https://github.com/notepad-plus-plus/notepad-plus-plus/commit/4f7563c7c7f8ffa0d7
- https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-
FAQ
What is CVE-2026-52885?
CVE-2026-52885 is a documented vulnerability. Notepad++ is a free and open-source source code editor. Prior to 8.9.6.4, NppCommands.cpp checks the HMAC of the on-disk shortcuts.xml at the moment a user command fires (Time-of-Check). However, the ...
How severe is CVE-2026-52885?
CVSS scoring is not yet available for CVE-2026-52885. Check NVD for updates.
Is there a patch for CVE-2026-52885?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.