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 3.1

7.8CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

0.2% chance of exploitation in the next 30 days; higher than 5% of CVEs (scores of 2026-10-26)

CWE

CWE-121

Published

2026-04-10

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

Affected

• notepad-plus-plus:notepad\+\+

References

• https://github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d68bc559534c046c4ef2d1865267aa2b0
• https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921
• https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930
• https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921

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