CVE-2026-5525
Stack-Based Buffer Overflow in Notepad++ File Drop Handler leads to DoS
Description
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).
INFO
Published Date :
April 10, 2026, 8:16 a.m.
Last Modified :
June 5, 2026, 1:54 p.m.
Remotely Exploit :
No
Source :
33c584b5-0579-4c06-b2a0-8d8329fcab9c
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 33c584b5-0579-4c06-b2a0-8d8329fcab9c | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Notepad++ to the latest version.
- Avoid dropping excessively long directory paths.
- Ensure proper bounds checking in file path handling.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-5525.
| URL | Resource |
|---|---|
| https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0 | Patch |
| https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 | Issue Tracking Exploit 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 | Issue Tracking Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5525 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-5525
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-5525 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5525 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 05, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:notepad-plus-plus:notepad++:8.9.3:*:*:*:*:*:*:* Added Reference Type securin: https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0 Types: Patch Added Reference Type CISA-ADP: https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 Types: Exploit, Issue Tracking, Mitigation, Vendor Advisory Added Reference Type securin: https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 Types: Exploit, Issue Tracking, Mitigation, Vendor Advisory Added Reference Type securin: https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930 Types: Issue Tracking, Patch -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 10, 2026
Action Type Old Value New Value Added Reference https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 -
New CVE Received by 33c584b5-0579-4c06-b2a0-8d8329fcab9c
Apr. 10, 2026
Action Type Old Value New Value Added Description 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). Added CVSS V3.1 AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N Added CWE CWE-121 Added Reference https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0 Added Reference https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 Added Reference https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930