Buffer overflow in Notepad-Plus-Plus Notepad\+\+
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).
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.0 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (7.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Notepad-Plus-Plus Notepad\+\+ — versions 8.9.3
- Notepad++ Project — versions 8.9.3, 8.9.4
Weakness classification (CWE)
References
- 33c584b5-0579-4c06-b2a0-8d8329fcab9c (Exploit, Mitigation, Issue Tracking, Vendor Advisory)
- 33c584b5-0579-4c06-b2a0-8d8329fcab9c (Patch, Issue Tracking)
- 33c584b5-0579-4c06-b2a0-8d8329fcab9c (Patch)
Frequently asked questions
- What is CVE-2026-5525?
- CVE-2026-5525 is a medium-severity vulnerability in Notepad-Plus-Plus Notepad\+\+, classified under Stack-based Buffer Overflow. CVSS score: 6.0/10. Published 2026-04-10.
- How severe is CVE-2026-5525?
- Medium severity. CVSS v3 base score is 6.0 out of 10.