CVE-2026-5525

A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. When a user drags and drops a directory path of exactly 259 characters without a trailing backslash, the application appends a backslash and null terminator without proper bounds checking, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).

CVSS v3 6.0 MEDIUM

6.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0	Patch
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921	Exploit Issue Tracking Mitigation Vendor Advisory
https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930	Issue Tracking Patch
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921	Exploit Issue Tracking Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-04-10 08:16

Updated : 2026-06-17 10:59

NVD link : CVE-2026-5525

Mitre link : CVE-2026-5525

CVE.ORG link : CVE-2026-5525

JSON object : View

Products Affected

notepad-plus-plus

notepad\+\+

CWE

CWE-121

Stack-based Buffer Overflow

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