CVE-2026-6539

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.

CVSS v3 4.4 MEDIUM

4.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://notepad-plus-plus.org/news/v894-released/	Release Notes
https://www.vulncheck.com/advisories/notepad-format-string-injection-via-nativelang-xml	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:notepad-plus-plus:notepad\+\+:8.9.3:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-30 21:16

Updated : 2026-06-17 11:00

NVD link : CVE-2026-6539

Mitre link : CVE-2026-6539

CVE.ORG link : CVE-2026-6539

JSON object : View

Products Affected

notepad-plus-plus

notepad\+\+

CWE

CWE-134

Use of Externally-Controlled Format String

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