CVE-2026-6539 MEDIUM

CVE-2026-6539: Notepad++ 8.9.3 Format String Injection via nativeLang.xml

Vendor Notepad++
Product Notepad++
Weakness CWE-134
Published April 30, 2026
Last update May 1, 2026

CVSS base score

4.6/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Notepad++ 8.9.3 contains a format string injection vulnerability in the Find Results panel handler that allows attackers to cause denial of service and information disclosure by crafting a malicious nativeLang.xml language pack file. Attackers can distribute a poisoned language pack through community channels that triggers format string interpretation when a user performs search operations, leading to access violations and potential leakage of stack or register contents.

Key dates

02Disclosure timeline

April 30, 2026 CVE published
May 1, 2026 Record updated