Vulnerability · Published Sep 22, 2026 · Assigned by GitHub_M
CVE-2026-85279Notepad++: Stack Buffer Overflow in Plugin Lexer Loading via Unchecked GetLexerCount() Return Value
High 8.6
In plain English
A high-severity stack buffer overflow in notepad-plus-plus from notepad-plus-plus. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).
Official description
Notepad++ is a free and open-source source code editor. Prior to 8.9.8, Notepad++ contains a stack buffer overflow in PluginsManager::loadPluginFromPath in PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp because the plugin-supplied GetLexerCount() result controls a loop that writes to containers[30] without enforcing NB_MAX_EXTERNAL_LANG. A malicious or compromised plugin that reports more than 30 lexers can write beyond the stack array and corrupt control data, which can permit arbitrary code execution in the Notepad++ process context. This issue is fixed in version 8.9.8.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| notepad-plus-plus | notepad-plus-plus | < 8.9.8 |
Weakness: CWE-121 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
References
- https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-h2wq-6x75-h8q2 x_refsource_CONFIRM
- https://github.com/notepad-plus-plus/notepad-plus-plus/commit/70b88f95311d88523cde6be1b1ec938aa48c24bc x_refsource_MISC
- https://github.com/notepad-plus-plus/notepad-plus-plus/commit/f1e1c71b090d69ca0f0175ab73895da41db67a16 x_refsource_MISC
- https://github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8 x_refsource_MISC
- https://notepad-plus-plus.org/news/v898-released x_refsource_MISC