High severity · published Sep 22, 2026
CVE-2026-85279
Notepad++: Stack Buffer Overflow in Plugin Lexer Loading via Unchecked GetLexerCount() Return Value
8.6
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
notepad-plus-plus · notepad-plus-plus
< 8.9.8 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-85279
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-85279
github.com
https://github.com/notepad-plus-plus/notepad-plus-plus/commit/70b88f95311d88523cde6be1b1ec938aa48c24bc
github.com
https://github.com/notepad-plus-plus/notepad-plus-plus/commit/f1e1c71b090d69ca0f0175ab73895da41db67a16
github.com
https://github.com/notepad-plus-plus/notepad-plus-plus/releases/tag/v8.9.8
github.com
https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-h2wq-6x75-h8q2
notepad-plus-plus.org
https://notepad-plus-plus.org/news/v898-released
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