CVE-2026-6539

Notepad++ 8.9.3 Format String Injection via nativeLang.xml

Published Apr 30, 2026 CVSS 4.0 · 4.6 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Don Ho
Don Ho notepad\+\+
CPEs cpe:2.3:a:don_ho:notepad\+\+:*:*:*:*:*:*:*:*
Vendors & Products Don Ho
Don Ho notepad\+\+
Type Values Removed Values Added
First Time appeared Notepad-plus-plus
Notepad-plus-plus notepad\+\+
CPEs cpe:2.3:a:notepad-plus-plus:notepad\+\+:8.9.3:*:*:*:*:*:*:*
Vendors & Products Notepad-plus-plus
Notepad-plus-plus notepad\+\+
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Notepad++
Notepad++ notepad++
Vendors & Products Notepad++
Notepad++ notepad++
Type Values Removed Values Added
Description 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.
Title Notepad++ 8.9.3 Format String Injection via nativeLang.xml
Weaknesses CWE-134
References
Metrics cvssV3_1

{'score': 4.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L'}

cvssV4_0

{'score': 4.6, '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Jul 28, 2026, 1:50 AM
Reserved
Apr 17, 2026, 5:20 PM
Status
Analyzed
Published
Apr 30, 2026, 9:16 PM
Modified
Nov 11, 2026, 9:10 PM