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).
Affected products
notepad-plus-plus: notepad\+\+
References4
- github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 ExploitIssue TrackingMitigationVendor Advisory
- github.com/notepad-plus-plus/notepad-plus-plus/issues/17921 ExploitIssue TrackingMitigationVendor Advisory
- github.com/notepad-plus-plus/notepad-plus-plus/commit/bfe7514d6… Patch
- github.com/notepad-plus-plus/notepad-plus-plus/pull/17930 Issue TrackingPatch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 12 November 2026
- CWE
- CWE-121
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