CVE-2026-5525

Name: CVE-2026-5525
Creator: NVD / NIST
Published: 2026-04-10T08:16:26.067+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 0.17%

Last modified Jun 17, 2026

CVE-2026-5525 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. 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).. EPSS estimates a 0.17% chance of exploitation in the next 30 days.

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).

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

0.17%

6.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-121

Affected Software

Vendor	Product	Versions
Notepad-Plus-Plus	Notepad\+\+	8.9.3

References

https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0Patch
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921Exploit, Issue Tracking, Mitigation, Vendor Advisory
https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930Issue Tracking, Patch
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921Exploit, Issue Tracking, Mitigation, Vendor Advisory

Timeline

Published: Apr 10, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-5525?

How severe is CVE-2026-5525?

CVE-2026-5525 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2026-5525?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-5525?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST